for Journals by Title or ISSN
for Articles by Keywords
help
  Subjects -> CHEMISTRY (Total: 845 journals)
    - ANALYTICAL CHEMISTRY (51 journals)
    - CHEMISTRY (595 journals)
    - CRYSTALLOGRAPHY (21 journals)
    - ELECTROCHEMISTRY (25 journals)
    - INORGANIC CHEMISTRY (41 journals)
    - ORGANIC CHEMISTRY (45 journals)
    - PHYSICAL CHEMISTRY (67 journals)

CHEMISTRY (595 journals)                  1 2 3 | Last

Showing 1 - 200 of 735 Journals sorted alphabetically
2D Materials     Hybrid Journal   (Followers: 8)
Accreditation and Quality Assurance: Journal for Quality, Comparability and Reliability in Chemical Measurement     Hybrid Journal   (Followers: 26)
ACS Catalysis     Full-text available via subscription   (Followers: 34)
ACS Chemical Neuroscience     Full-text available via subscription   (Followers: 18)
ACS Combinatorial Science     Full-text available via subscription   (Followers: 23)
ACS Macro Letters     Full-text available via subscription   (Followers: 24)
ACS Medicinal Chemistry Letters     Full-text available via subscription   (Followers: 39)
ACS Nano     Full-text available via subscription   (Followers: 244)
ACS Photonics     Full-text available via subscription   (Followers: 11)
ACS Synthetic Biology     Full-text available via subscription   (Followers: 21)
Acta Chemica Iasi     Open Access   (Followers: 2)
Acta Chimica Sinica     Full-text available via subscription   (Followers: 1)
Acta Chimica Slovaca     Open Access   (Followers: 1)
Acta Chromatographica     Full-text available via subscription   (Followers: 9)
Acta Facultatis Medicae Naissensis     Open Access  
Acta Metallurgica Sinica (English Letters)     Hybrid Journal   (Followers: 5)
Acta Scientifica Naturalis     Open Access   (Followers: 2)
adhäsion KLEBEN & DICHTEN     Hybrid Journal   (Followers: 5)
Adhesion Adhesives & Sealants     Hybrid Journal   (Followers: 8)
Adsorption Science & Technology     Full-text available via subscription   (Followers: 5)
Advanced Functional Materials     Hybrid Journal   (Followers: 51)
Advanced Science Focus     Free   (Followers: 3)
Advances in Chemical Engineering and Science     Open Access   (Followers: 56)
Advances in Chemical Science     Open Access   (Followers: 13)
Advances in Chemistry     Open Access   (Followers: 15)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 18)
Advances in Drug Research     Full-text available via subscription   (Followers: 22)
Advances in Enzyme Research     Open Access   (Followers: 9)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 8)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 16)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 9)
Advances in Materials Physics and Chemistry     Open Access   (Followers: 21)
Advances in Nanoparticles     Open Access   (Followers: 15)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 15)
Advances in Polymer Science     Hybrid Journal   (Followers: 41)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 17)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 20)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 5)
Advances in Science and Technology     Full-text available via subscription   (Followers: 12)
African Journal of Bacteriology Research     Open Access  
African Journal of Chemical Education     Open Access   (Followers: 2)
African Journal of Pure and Applied Chemistry     Open Access   (Followers: 7)
Agrokémia és Talajtan     Full-text available via subscription   (Followers: 2)
Alkaloids: Chemical and Biological Perspectives     Full-text available via subscription   (Followers: 3)
AMB Express     Open Access   (Followers: 1)
Ambix     Hybrid Journal   (Followers: 3)
American Journal of Biochemistry and Biotechnology     Open Access   (Followers: 67)
American Journal of Biochemistry and Molecular Biology     Open Access   (Followers: 14)
American Journal of Chemistry     Open Access   (Followers: 27)
American Journal of Plant Physiology     Open Access   (Followers: 14)
American Mineralogist     Hybrid Journal   (Followers: 14)
Analyst     Full-text available via subscription   (Followers: 40)
Angewandte Chemie     Hybrid Journal   (Followers: 203)
Angewandte Chemie International Edition     Hybrid Journal   (Followers: 219)
Annales UMCS, Chemia     Open Access   (Followers: 1)
Annals of Clinical Chemistry and Laboratory Medicine     Open Access   (Followers: 4)
Annual Reports in Computational Chemistry     Full-text available via subscription   (Followers: 3)
Annual Reports Section A (Inorganic Chemistry)     Full-text available via subscription   (Followers: 4)
Annual Reports Section B (Organic Chemistry)     Full-text available via subscription   (Followers: 8)
Annual Review of Chemical and Biomolecular Engineering     Full-text available via subscription   (Followers: 12)
Annual Review of Food Science and Technology     Full-text available via subscription   (Followers: 15)
Anti-Infective Agents     Hybrid Journal   (Followers: 3)
Antiviral Chemistry and Chemotherapy     Hybrid Journal  
Applied Organometallic Chemistry     Hybrid Journal   (Followers: 7)
Applied Spectroscopy     Full-text available via subscription   (Followers: 23)
Applied Surface Science     Hybrid Journal   (Followers: 28)
Arabian Journal of Chemistry     Open Access   (Followers: 6)
ARKIVOC     Open Access   (Followers: 2)
Asian Journal of Biochemistry     Open Access   (Followers: 1)
Atomization and Sprays     Full-text available via subscription   (Followers: 4)
Australian Journal of Chemistry     Hybrid Journal   (Followers: 7)
Autophagy     Hybrid Journal   (Followers: 2)
Avances en Quimica     Open Access   (Followers: 1)
Biochemical Pharmacology     Hybrid Journal   (Followers: 10)
Biochemistry     Full-text available via subscription   (Followers: 310)
Biochemistry Insights     Open Access   (Followers: 6)
Biochemistry Research International     Open Access   (Followers: 6)
BioChip Journal     Hybrid Journal  
Bioinorganic Chemistry and Applications     Open Access   (Followers: 9)
Bioinspired Materials     Open Access   (Followers: 5)
Biointerface Research in Applied Chemistry     Open Access   (Followers: 2)
Biointerphases     Open Access   (Followers: 1)
Biology, Medicine, & Natural Product Chemistry     Open Access   (Followers: 1)
Biomacromolecules     Full-text available via subscription   (Followers: 19)
Biomass Conversion and Biorefinery     Partially Free   (Followers: 10)
Biomedical Chromatography     Hybrid Journal   (Followers: 6)
Biomolecular NMR Assignments     Hybrid Journal   (Followers: 3)
BioNanoScience     Partially Free   (Followers: 5)
Bioorganic & Medicinal Chemistry     Hybrid Journal   (Followers: 118)
Bioorganic & Medicinal Chemistry Letters     Hybrid Journal   (Followers: 91)
Bioorganic Chemistry     Hybrid Journal   (Followers: 10)
Biopolymers     Hybrid Journal   (Followers: 18)
Biosensors     Open Access   (Followers: 2)
Biotechnic and Histochemistry     Hybrid Journal   (Followers: 1)
Bitácora Digital     Open Access  
Boletin de la Sociedad Chilena de Quimica     Open Access  
Bulletin of the Chemical Society of Ethiopia     Open Access   (Followers: 2)
Bulletin of the Chemical Society of Japan     Full-text available via subscription   (Followers: 24)
Bulletin of the Korean Chemical Society     Hybrid Journal   (Followers: 1)
C - Journal of Carbon Research     Open Access   (Followers: 3)
Cakra Kimia (Indonesian E-Journal of Applied Chemistry)     Open Access  
Canadian Association of Radiologists Journal     Full-text available via subscription   (Followers: 3)
Canadian Journal of Chemistry     Hybrid Journal   (Followers: 10)
Canadian Mineralogist     Full-text available via subscription   (Followers: 4)
Carbohydrate Research     Hybrid Journal   (Followers: 26)
Carbon     Hybrid Journal   (Followers: 66)
Catalysis for Sustainable Energy     Open Access   (Followers: 7)
Catalysis Reviews: Science and Engineering     Hybrid Journal   (Followers: 8)
Catalysis Science and Technology     Free   (Followers: 7)
Catalysis Surveys from Asia     Hybrid Journal   (Followers: 3)
Catalysts     Open Access   (Followers: 8)
Cellulose     Hybrid Journal   (Followers: 7)
Cereal Chemistry     Full-text available via subscription   (Followers: 4)
ChemBioEng Reviews     Full-text available via subscription   (Followers: 1)
ChemCatChem     Hybrid Journal   (Followers: 8)
Chemical and Engineering News     Free   (Followers: 14)
Chemical Bulletin of Kazakh National University     Open Access  
Chemical Communications     Full-text available via subscription   (Followers: 72)
Chemical Engineering Research and Design     Hybrid Journal   (Followers: 24)
Chemical Research in Chinese Universities     Hybrid Journal   (Followers: 3)
Chemical Research in Toxicology     Full-text available via subscription   (Followers: 20)
Chemical Reviews     Full-text available via subscription   (Followers: 182)
Chemical Science     Open Access   (Followers: 22)
Chemical Technology     Open Access   (Followers: 16)
Chemical Vapor Deposition     Hybrid Journal   (Followers: 5)
Chemical Week     Full-text available via subscription   (Followers: 8)
Chemie in Unserer Zeit     Hybrid Journal   (Followers: 58)
Chemie-Ingenieur-Technik (Cit)     Hybrid Journal   (Followers: 26)
ChemInform     Hybrid Journal   (Followers: 8)
Chemistry & Biodiversity     Hybrid Journal   (Followers: 6)
Chemistry & Biology     Full-text available via subscription   (Followers: 30)
Chemistry & Industry     Hybrid Journal   (Followers: 5)
Chemistry - A European Journal     Hybrid Journal   (Followers: 146)
Chemistry - An Asian Journal     Hybrid Journal   (Followers: 15)
Chemistry and Materials Research     Open Access   (Followers: 20)
Chemistry Central Journal     Open Access   (Followers: 4)
Chemistry Education Research and Practice     Free   (Followers: 5)
Chemistry in Education     Open Access   (Followers: 9)
Chemistry International     Hybrid Journal   (Followers: 2)
Chemistry Letters     Full-text available via subscription   (Followers: 44)
Chemistry of Materials     Full-text available via subscription   (Followers: 258)
Chemistry of Natural Compounds     Hybrid Journal   (Followers: 9)
Chemistry World     Full-text available via subscription   (Followers: 22)
Chemistry-Didactics-Ecology-Metrology     Open Access   (Followers: 1)
ChemistryOpen     Open Access   (Followers: 2)
Chemkon - Chemie Konkret, Forum Fuer Unterricht Und Didaktik     Hybrid Journal  
Chemoecology     Hybrid Journal   (Followers: 4)
Chemometrics and Intelligent Laboratory Systems     Hybrid Journal   (Followers: 15)
Chemosensors     Open Access  
ChemPhysChem     Hybrid Journal   (Followers: 9)
ChemPlusChem     Hybrid Journal   (Followers: 2)
ChemTexts     Hybrid Journal  
CHIMIA International Journal for Chemistry     Full-text available via subscription   (Followers: 2)
Chinese Journal of Chemistry     Hybrid Journal   (Followers: 6)
Chinese Journal of Polymer Science     Hybrid Journal   (Followers: 10)
Chromatographia     Hybrid Journal   (Followers: 24)
Clay Minerals     Full-text available via subscription   (Followers: 10)
Cogent Chemistry     Open Access  
Colloid and Interface Science Communications     Open Access  
Colloid and Polymer Science     Hybrid Journal   (Followers: 10)
Colloids and Surfaces B: Biointerfaces     Hybrid Journal   (Followers: 7)
Combinatorial Chemistry & High Throughput Screening     Hybrid Journal   (Followers: 4)
Combustion Science and Technology     Hybrid Journal   (Followers: 18)
Comments on Inorganic Chemistry: A Journal of Critical Discussion of the Current Literature     Hybrid Journal   (Followers: 2)
Composite Interfaces     Hybrid Journal   (Followers: 6)
Comprehensive Chemical Kinetics     Full-text available via subscription   (Followers: 2)
Comptes Rendus Chimie     Full-text available via subscription  
Comptes Rendus Physique     Full-text available via subscription   (Followers: 1)
Computational and Theoretical Chemistry     Hybrid Journal   (Followers: 9)
Computational Biology and Chemistry     Hybrid Journal   (Followers: 12)
Computational Chemistry     Open Access   (Followers: 2)
Computers & Chemical Engineering     Hybrid Journal   (Followers: 9)
Coordination Chemistry Reviews     Full-text available via subscription   (Followers: 3)
Copernican Letters     Open Access   (Followers: 1)
Critical Reviews in Biochemistry and Molecular Biology     Hybrid Journal   (Followers: 5)
Crystal Structure Theory and Applications     Open Access   (Followers: 4)
CrystEngComm     Full-text available via subscription   (Followers: 13)
Current Catalysis     Hybrid Journal   (Followers: 2)
Current Metabolomics     Hybrid Journal   (Followers: 5)
Current Opinion in Colloid & Interface Science     Hybrid Journal   (Followers: 9)
Current Opinion in Molecular Therapeutics     Full-text available via subscription   (Followers: 17)
Current Research in Chemistry     Open Access   (Followers: 8)
Current Science     Open Access   (Followers: 61)
Dalton Transactions     Full-text available via subscription   (Followers: 23)
Detection     Open Access   (Followers: 2)
Developments in Geochemistry     Full-text available via subscription   (Followers: 2)
Diamond and Related Materials     Hybrid Journal   (Followers: 12)
Dislocations in Solids     Full-text available via subscription  
Doklady Chemistry     Hybrid Journal  
Drying Technology: An International Journal     Hybrid Journal   (Followers: 4)
Eclética Química     Open Access   (Followers: 1)
Ecological Chemistry and Engineering S     Open Access   (Followers: 3)
Ecotoxicology and Environmental Contamination     Open Access  
Educación Química     Open Access   (Followers: 1)
Education for Chemical Engineers     Hybrid Journal   (Followers: 5)
EJNMMI Radiopharmacy and Chemistry     Open Access  
Elements     Full-text available via subscription   (Followers: 3)
Environmental Chemistry     Hybrid Journal   (Followers: 7)
Environmental Chemistry Letters     Hybrid Journal   (Followers: 4)
Environmental Science & Technology Letters     Full-text available via subscription   (Followers: 5)

        1 2 3 | Last

Journal Cover Applied Organometallic Chemistry
  [SJR: 0.632]   [H-I: 58]   [7 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0268-2605 - ISSN (Online) 1099-0739
   Published by John Wiley and Sons Homepage  [1579 journals]
  • Podophyllotoxin extraction from Linum usitatissimum plant and its
           anticancer activity against HT-29, A-549 and MDA-MB-231 cell lines with
           and without the presence of gold nanoparticles
    • Authors: Mohammad Safarpoor; Mehrorang Ghaedi, Masoume Yousefinejad, Hamedreza Javadian, Arash Asfaram, Zahra Ghasemi, Hajar Jaberi, Daruosh Rahimi
      Abstract: In recent years, gold nanoparticles (Au-NPs) have been taken into consideration in nanomedicine due to their excellent biocompatibility, chemical stability and promising optical properties. In this research, podophyllotoxin conjugated with gold nanoparticles (Au-NPs-POT) was synthesized and the conjugation of POT with Au-NPs was confirmed using scanning electron microscopy, mass spectrometry and Fourier transform infrared spectroscopy. The anticancer effects of the product on preclinical models of lung, colon and breast cancers were investigated using MTT test. The analyses showed a direct dose–response relationship. It was found that higher concentrations of POT have more positive effects on the inhibition of cancer cell growth. At POT concentrations of 1, 2.5, 5, 7.5, 10, 15 and 20 mg ml−1, approximately 50% of the growth of colorectal, lung and breast cancer cell lines was inhibited, while similar results were obtained in the presence of 1, 2, 3, 4 and 5 μg ml−1 Au-NPs-POT. Au-NPs-POT exhibited the lowest cytotoxicity due to the presence of POT. The anticancer feature of Au-NPs-POT proved the potential to develop better anticancer therapeutics and to open new avenues for treatment of cancers.In cell culture studies, the anti-cancer effect of podophyllotoxin – extracted from the flax oil –on colon, lung, and breast cancer cell lines, as well as normal cell lines Vero (African green monkey kidney) was examined, both in the presence and absence of gold nanoparticles.
      PubDate: 2017-11-09T05:42:42.97228-05:0
      DOI: 10.1002/aoc.4024
       
  • Single and binary catalyst systems based on nickel and palladium in
           polymerization of ethylene
    • Authors: Mahsa Kimiaghalam; Hossein Nasr Isfahani, Gholam Hossein Zohuri, Ali Keivanloo
      Abstract: The catalyst (N,N-bis(2,6-dibenzhydryl-4-ethoxyphenyl)butane-2,3-diimine)nickel dibromide, a late transition metal catalyst, was prepared and used in ethylene polymerization. The effects of reaction parameters such as polymerization temperature, co-catalyst to catalyst molar ratio and monomer pressure on the polymerization were investigated. The α-diimine nickel-based catalyst was demonstrated to be thermally robust at a temperature as high as 90 °C. The highest activity of the catalyst (494 kg polyethylene (mol cat)−1 h−1) was obtained at [Al]/[Ni] = 600:1, temperature of 90 °C and pressure of 5 bar. In addition, the performance of a binary catalyst using nickel- and palladium-based complexes was compared with that of the corresponding individual catalytic systems in ethylene polymerization. In a study of the catalyst systems, the average molecular weight and molecular weight distribution for the binary polymerization were between those for the individual catalytic polymerizations; however, the binary catalyst activity was lower than that of the two individual ones. The obtained polyethylenes had high molecular weights in the region of 105 g mol−1. Gel permeation chromatography analysis showed a narrow molecular weight distribution of 1.44 for the nickel-based catalyst and 1.61 for the binary catalyst system. The branching density of the polyethylenes generated using the binary catalytic system (30 branches/1000 C) was lower than that generated using the nickel-based catalyst (51/1000 C). X-ray diffraction study of the polymer chains showed higher crystallinity with lower branching of the polymer obtained. Also Fourier transform infrared spectra confirmed that all obtained polymers were low-density polyethylene.A benzhydryl-derived ligand framework and the corresponding nickel(II) α-diimine complex were synthesized, characterized and the complex used in ethylene polymerization. High thermal stability of the complex was a significant aspect. The performance of a binary catalyst system involving nickel and palladium complexes in polymerization was compared with that of corresponding single catalysts. The branching of polyethylene obtained in the presence of the binary catalyst was lower compared to corresponding individual catalytic systems.
      PubDate: 2017-11-09T05:36:12.430051-05:
      DOI: 10.1002/aoc.4153
       
  • Computational insight into asymmetric uranyl-salophen coordinated with α,
           β-unsaturated aldehydes and ketones
    • Authors: Wen-Bo Lan; Xiao-Feng Wang, Li-Ping He, Yan-Bin Meng, Jun Li, Bin Qiu, Chang-Ming Nie
      Abstract: The study of the catalytic activity and activation mechanism of asymmetric uranyl-salophens with α, β-unsaturated aldehydes or α, β-unsaturated ketones, is a research hotspot. In this paper, the complexes of the uranyl–salophen(U-S) modified by unilateral benzene, coordinated with cyclohexenone, cyclopentenone and acrolein, were investigated using density functional theory calculations at the level of B3LYP/6-311G(d, p) basis set. The results showed that the uranyl-salophen(U-S) weakened the large π bond between C = C and C = O of the α, β-unsaturated aldehydes and ketones, making the unsaturated aldehydes and ketones activated. In addition, the molecular-recognition selectivity of the asymmetrical uranyl-salophen for cyclohexenone and cyclopentenone were much higher than for acrolein.The asymmetrical uranyl-salophen have the molecular-recognition selectivity for the α, β-unsaturated aldehydes and ketones and could weaken the large the π bond between C = C and C = O of the α, β-unsaturated aldehydes and ketones.
      PubDate: 2017-11-09T05:35:52.083935-05:
      DOI: 10.1002/aoc.4137
       
  • Suzuki–Miyaura coupling catalyzed by palladium nanoparticles
           
    • Authors: Hojat Veisi; Mehdi Adib, Rahman Karimi-Nami, Zahra Yasaei, Mahnaz Tajik, Talieh Sadat Mosavat, Saba Hemmati
      Abstract: An unprecedented environmentally friendly method has been developed for the synthesis of palladium nanoparticles supported on Glycyrrhiza glabra. The synthesized nanoparticles were utilized in Suzuki–Miyaura reaction between different aryl halides and aryl bronic acid in aqueous media. This heterogeneous catalyst can be reused and recycled repeatedly more than five times with only slight loss of its initial catalytic efficiency. This reaction carrid out under atmospheric pressure with high efficiency, unique and simple work-up procedure and excellent yields.An environmentally friendly method has been developed for the synthesis of palladium nanoparticles supported on Glycyrrhiza glabra as green nanocatalyst in the Suzuki–Miyaura reactions.
      PubDate: 2017-11-09T05:26:29.170305-05:
      DOI: 10.1002/aoc.4138
       
  • Application of a dispersive micro-solid-phase extraction method for
           pre-concentration and ultra-trace determination of cadmium ions in water
           and biological samples
    • Authors: Mohammad Behbahani; Ali Veisi, Fariborz Omidi, Aminreza Noghrehabadi, Ali Esrafili, Mohammad Hossein Ebrahimi
      Abstract: A method for the trace determination of cadmium ions in water, human urine and human blood serum samples using ultrasonic-assisted dispersive micro-solid-phase extraction (UA-D-μSPE) was developed. Silica-coated magnetic nanoparticles were coated with polythiophene, and the resulting sorbent was characterized using thermogravimetry, differential thermal analysis, scanning electron microscopy, Fourier transform infrared spectrometry and X-ray diffraction. Following UA-D-μSPE, cadmium ions were quantified using graphite furnace atomic absorption spectrometry. A Box–Behnken design was used for optimization of important sorption and desorption parameters in UA-D-μSPE: in the sorption step, pH of solution, sorption amount and sonication time for sorption; in the desorption step, concentration of eluent, volume of eluent and sonication time. The optimum conditions for the method were: pH of solution, 7.5; sonication time for sorption, 3 min; sorption amount, 35 mg; type and concentration of eluent, HCl and 1.1 mol l−1; volume of eluent, 360 μl; sonication time for desorption, 110 s. Under the optimized conditions the limit of detection and relative standard deviation for the detection of cadmium ions by UA-D-μSPE were found to be 0.8 ng l−1 and
      PubDate: 2017-11-09T05:21:20.298308-05:
      DOI: 10.1002/aoc.4134
       
  • The investigation of Ag decorated double-wall hollow TiO2 spheres as
           photocatalyst
    • Authors: Chao Zhang; Yuming Zhou, Yiwei Zhang, Shuo Zhao, Jiasheng Fang, Xiaoli Sheng
      Abstract: In this paper, a novel TiO2 nanosheets assembled double-wall hollow sphere (DHS)has been prepared successfully via hydrothermal treatment of SiO2@TiO2 with the assistant of CTAB.The prepared samples are characterized with transmission electron microscopy (TEM), scanning electron microscopy (SEM), electron spin resonance (ESR), X-ray diffraction (XRD) and X-ray photoelectron spectra (XPS), etc.Results show that redeposited silica species play a key role in the formation of the double-wall structure. The as-synthesized DHS nanostructure exhibits a large surface area (417.6 m2 g-1) and excellent mechanical strength. Furthermore, after decoration of Ag and calcination treatment, the double-shelled TiO2/Ag heterostructures show an enhanced photocatalytic performance in the degradation of RhB under UV or visible light irradiations for the following reasons: the surface plasmon resonance effect of Ag, strong interaction between Ag and TiO2 nanosheets, large surface area, excellent adsorption capacityand unique double-wall structure. On the basis of the experimental results, a possible mechanism for pollutantdegradation under visual light irradiation has been proposed.It is a novel strategy to construct double-wall TiO2 hollow spheres.The nanostructures are assembled with TiO2 nanosheets and show a large surface area.The Ag decorated double-wall nanomaterials exhibits an excellent photocatalytic performance.
      PubDate: 2017-11-09T05:17:02.432814-05:
      DOI: 10.1002/aoc.4160
       
  • Structure and applications of organotin complex based on trimethyltin
           cation and quinaldic acid
    • Authors: Mohamed M. El-bendary; Safaa El-din H. Etaiw
      Abstract: The reaction between aqueous solution of Me3SnCl and acetonitrile solution of quinaldic acid (quinH) at room temperature affords a new organotin complex, [Me3Sn(quinH)(quin)]⋅6H2O (1). Complex 1 was structurally characterized using infrared, UV–visible and NMR spectra, thermogravimetric analysis and single-crystal X-ray analysis. The network structure of 1 is developed by a limitless number of discrete mononuclear molecules forming a one-dimensional chain via hydrogen bonds. Extensive hydrogen bonds and π–π stacking associate the one-dimensional chains creating a two-dimensional array. The two-dimensional arrays are additionally associated via hydrogen bonds through the water molecules and the methyl groups forming a three-dimensional network. The cytotoxic impact of 1 on the viability of MCF-7 cells was also examined using MTT assay, exhibiting great inhibiting action against MCF-7 cells. Furthermore, the catalytic degradation performance of 1 towards methylene blue dye in the presence of H2O2 as oxidant was investigated. The reaction is first order with respect to methylene blue dye.The three-dimensional network structure of organotin complex [Me3Sn(quinH)(quin)]⋅6H2O (1) is developed by extensive hydrogen bonding and π–π stacking. Organotin complex 1 exhibits great inhibiting action against MCF-7 cells. Complex 1 can be also considered as an efficient heterogeneous catalyst for elimination of methylene blue dye.
      PubDate: 2017-11-09T05:11:29.482388-05:
      DOI: 10.1002/aoc.4152
       
  • Novel ultrasonic-assisted deep eutectic solvent-based dispersive
           liquid–liquid microextraction for determination of vanadium in food
           samples by electrothermal atomic absorption spectrometry: A multivariate
           study
    • Authors: Rizwan Ali Zounr; Mustafa Tuzen, Muhammad Yar Khuhawar
      Abstract: A green, efficient, simple and sensitive pre-concentration method has been developed for the determination of vanadium(V) in foodstuffs using deep eutectic solvent–ultrasonic-assisted dispersive liquid–liquid microextraction. In the developed procedure, the extraction of vanadium(V) was achieved using 2-hydroxy-3-methoxybenzaldehyde thiosemicarbazone as a chelating agent, choline chloride–phenol as extracting solvent and tetrahydrofuran as dispersive solvent. Vanadium(V) concentration was measured using electrothermal atomic absorption spectrometry. Various analytical parameters including pH, type and molar ratio of deep eutectic solvent, ultrasonication time and amount of ligand were studied. A multivariate study was carried out for optimization of the variables. The pre-concentration factor was calculated as 50. Under optimal conditions, limit of detection, limit of quantification and relative standard deviation were calculated as 0.025 μg l−1, 0.175 μg l−1 and 3.4%, respectively. The accuracy of the procedure was confirmed using certified reference materials and standard addition method. The obtained results confirm adequate recoveries for vanadium(V) (>96%). This technique was fruitfully applied for determination of vanadium in foodstuffs.A novel ultrasonic assisted-deep eutectic solvent based on dispersive liquid liquid microextraction of vanadium in food samples by electrothermal atomic absorption spectroscopy.
      PubDate: 2017-11-09T05:10:45.296087-05:
      DOI: 10.1002/aoc.4144
       
  • Adsorption of metal ions by microwave assisted grafting of cross-linked
           chitosan beads. Equilibrium, isotherm, thermodynamic and desorption
           studies
    • Authors: E. Igberase; P. Osifo, A. Ofomaja
      Abstract: Chemical modification of chitosan has become increasingly essential due to chitosan versatility that enables the material to be easily modified in a way of increasing its properties in adsorption processes. In this investigation, chitosan solution was cross-linked with glutaraldehyde the cross-linked solution was used in producing the beads and thereafter grafted with ethylene acrylic acid. The chemical functionalities of the beads were obtained by Fourier transform infrared spectroscopy (FTIR), Scanning electron microscope (SEM), X-ray diffraction (XRD) and Thermogravimetric analysis (TGA). Adsorption of Pb2+, Cu2+, Ni2+, Zn2+, Cr6+ and Cd2+ ions from single component aqueous mixture by grafted cross-linked chitosan beads (GXXB) was studied as a function of pH, temperature, initial concentration, contact time, agitation speed and ionic strength. Equilibrium data was obtained from the adsorption experiment, the data were applied in isotherm, thermodynamics and kinetic studies. The Langmuir, Temkin and Dubinin-kaganer-Radushkevich (DKR) model were successful in describing the isotherm data for the considered metal ions while the Freundlich model was not efficient in describing the experimental data. Pseudo-second order and intra-particle model described the kinetic data quite well. Thermodynamic parameters such as Gibb's free energy change (∆Go), enthalpy change (∆Ho) and entropy change (∆So) were calculated and the results showed the adsorption of Pb2+, Cu2+, Ni2+, Zn2+, Cr6+ and Cd2+ ions onto GXXB is spontaneous and endothermic in nature. Regeneration of the used adsorbent was effective for the studied metal ions.Chitosan beads production process.
      PubDate: 2017-11-09T05:06:00.565525-05:
      DOI: 10.1002/aoc.4131
       
  • Application and developing of iron-doped multi-walled carbon nanotubes
           (Fe/MWCNTs) as an efficient and reusable heterogeneous nanocatalyst in the
           synthesis of heterocyclic compounds
    • Authors: Hashem Sharghi; Jasem Aboonajmi, Mozhdeh Mozaffari, Mohammad Mahdi Doroodmand, Mahdi Aberi
      Abstract: Iron-doped multi-walled carbon nanotubes (Fe/MWCNTs) is an efficient, ecofriendly and reusable heterogeneous nanocatalyst for the one-pot synthesis of heterocyclic compounds including bis-spiro piperidines, piperidines, dihydro-2-oxopyrroles, pyrazoles and diazepines at room temperature with good to excellent yields. The heterogeneous nanocatalyst was fully characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), inductively coupled plasma (ICP) and FT-IR analysis. Also, the structures of all prepared compounds were characterized by 1H NMR, 13C NMR, FT-IR, mass spectrometry (MS) and elemental analysis. The major advantages of these protocols are mild and green reaction conditions, short reaction times, clean reaction, operational simplicity, easy purification and good to excellent yields with the reusable heterogeneous nanocatalyst. The catalyst was ten recycled without significant loss of activity.Iron-doped multi-walled carbon nanotubes (Fe/MWCNTs) is an efficient, ecofriendly and reusable heterogeneous nanocatalyst for the one-pot synthesis of heterocyclic compounds including bis-spiro piperidines, piperidines, dihydro-2-oxopyrroles, pyrazoles and diazepines at mild conditions with good to excellent yields. The heterogeneous nanocatalyst was fully characterized. The major advantages of these protocols are mild and green reaction conditions, short reaction times, clean reaction, operational simplicity, easy purification and good to excellent yields. The catalyst was ten recycled without significant loss of activity.
      PubDate: 2017-11-09T04:56:53.466363-05:
      DOI: 10.1002/aoc.4124
       
  • Copper–birhodanine complex immobilized on Fe3O4 nanoparticles: DFT
           studies and heterogeneous catalytic applications in the synthesis of
           propargylamines in aqueous medium
    • Authors: Manuchehr Rezaei; Khaled Azizi, Kamal Amani
      Abstract: Heterogeneous magnetic nanocatalyst, Fe3O4@SiO2–Ligand–Cu (II) MNPs, reveals high catalytic performance within the synthesis of propargylamines using the multicomponent coupling reaction of aldehydes, phenylacetylene and secondary amines in water as a solvent. The substantial feature of this organic–inorganic hybrid magnetic nanocatalyst is the capability of straightforward separation of the reaction mixture by an external magnet which was retrieved ten times without significant loss of catalytic activity. This methodology has other advantages such as subordination to the principles of green chemistry and avoiding the use of expensive and harmful organic solvents. To study the stability and actual structure of birhodanine derivative–copper (II) complex, DFT calculations were also performed.More recent prepared heterogeneous magnetic nanocatalyst, Fe3O4@SiO2–Ligand–Cu (II) MNPs, reveals high catalytic performance within the synthesis of propargylamines using the multicomponent coupling reaction of aldehydes, phenylacetylene and secondary amines in water as a solvent. Subordination to the principles of green chemistry and avoiding the use of expensive and harmful organic solvents are advantages of this methodology.
      PubDate: 2017-11-09T04:36:17.016827-05:
      DOI: 10.1002/aoc.4120
       
  • Zinc oxide nanorod-loaded activated carbon for ultrasound-assisted
           adsorption of safranin O: Central composite design and genetic algorithm
           optimization
    • Authors: E. Sharifpour; M. Ghaedi, F. Nasiri Azad, K. Dashtian, H. Hadadi, M.K. Purkait
      Abstract: This paper focuses on the development of an effective methodology to obtain the optimum ultrasonic-assisted removal of a dye, safranin O (SO), under optimum conditions that maximize the removal percentage, using ZnO nanorod-loaded activated carbon (ZnO-NRs-AC) in aqueous solution. Central composite design coupled with genetic algorithm was used for parameter optimization. The effects of variables such as pH, initial dye concentration, mass of ZnO-NRs-AC and sonication time were studied. The interactive and main effects of these variables were evaluated using analysis of variance. The structural and physicochemical properties of the ZnO-NRs-AC adsorbent were investigated using field emission scanning electron microscopy and X-ray diffraction. Adsorption equilibrium data were fitted well with the Langmuir isotherm and the maximum monolayer capacity was found to be 32.06 mg g−1. Studies of the adsorption kinetics of the SO dye showed a rapid sorption dynamic with a pseudo-second-order kinetic model, suggesting a chemisorption mechanism.This paper focuses on the development of an effective methodology to obtain the optimum conditions for ultrasonic-assisted removal of safranin O dye that maximize the removal using ZnO nanorod-loaded activated carbon in aqueous solution. Central composite design coupled with genetic algorithm was used for parameter optimization.
      PubDate: 2017-11-09T04:31:21.751782-05:
      DOI: 10.1002/aoc.4099
       
  • Schiff base supported mononuclear organotin(IV) complexes: Syntheses,
           structures and fluorescence cell imaging
    • Authors: Richa Vinayak; Dhritiman Dey, Dipanjan Ghosh, Dhrubajyoti Chattopadhyay, Abhrajyoti Ghosh, Hari Pada Nayek
      Abstract: Three mononuclear organotin(IV) complexes supported by Schiff bases have been synthesized. The complexes [(C6H5)2Sn(L)] (1), [(t-Bu)2Sn(L)] (2) and [(t-Bu)2Sn(L')] (3) (L, L' = deprotonated Schiff bases) were obtained in good yield by the reaction of Schiff bases H2L or H2L′ with corresponding diorganotin dichlorides respectively. All newly synthesized complexes were characterized by means of FT-IR spectroscopy, elemental analysis and multinuclear (1H, 13C and 119Sn) NMR spectroscopy. In addition, single crystal X-ray diffraction analyses were employed to establish the solid state molecular structures of these complexes. The structures of 1–3 reveal that all complexes are mononuclear with a five-coordinated tin(IV) centre in it. The absorption and emission properties of all complexes have been investigated. Moreover, cytotoxicity and fluorescence cell imaging studies of theses complexes have been performed.Mononuclear organotin(IV) compounds exhibiting strong fluorescence have been employed for fluorescence cell imaging. Compounds with aliphatic substitution on tin atom were more effective bio-imaging agents compared to its aromatic derivatives.
      PubDate: 2017-11-09T04:30:48.249302-05:
      DOI: 10.1002/aoc.4122
       
  • Synthesis, spectral characterization, thermal studies and biological
           activity of
           (Z)-5-((1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)diazenyl)-6-hydroxy-2-mercaptopyrimidin-4(3H)-one
           and its metal complexes
    • Authors: Sanaa M. Emam; Saeyda A. Abouel-Enein, Fatma I. Abouzayed
      Abstract: (Z)-5-((1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)diazenyl)-6-hydroxy-2-mercaptopyrimidin-4(3H)-one (H3L) was exploited as a ligand for the synthesis of a series of metal complexes, where the metal was Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Pd(II), Cr(III) and Ru(III). The structural features of the ligand and the synthesized complexes were characterized using various analytical, spectral and thermal measurements. Infrared spectra showed that the ligand coordinates to all metal ions in a neutral keto–enol–thiol manner. It behaves in a tetradentate fashion in all binuclear complexes except the Cr(III) complex, where it is hexadentate, and in a tridentate fashion in mononuclear complexes. The azo group participates in chelation only in the case of binuclear complexes. All complexes exhibit octahedral geometry except Pd(II) and Cu(II) acetate which are square planar and square pyramidal, respectively. Kinetic parameters were computed from thermal decomposition data. Axial electron spin resonance spectra were obtained for Cu(II) complexes indicating (dx2−y2)1 as a ground state with small g values affording strong interaction between the ligand and metal ions. The biological measurements reveal that the ligand has antioxidant activity relative to the metal complexes, while the metal complexes have cytotoxicity in comparison to the free ligand.(Z)-5-((1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)diazenyl)-6-hydroxy-2-mercaptopyrimidin-4(3H)-one (H3L)
      PubDate: 2017-11-03T06:35:59.125693-05:
      DOI: 10.1002/aoc.4073
       
  • MNPs@SiO2-Pr-AP: A new catalyst for the synthesis of 2-amino-4-aryl
           thiazole derivatives
    • Authors: Ramin Ghorbani-Vaghei; Sedigheh Alavinia, Zohreh Merati, Vida Izadkhah
      Abstract: A simple and efficient synthesis of 2-amino-4-aryl thiazole derivatives was carried out through the reaction of substituted acetophenones and thiourea using three different types of catalytic systems including N,N,N′,N′-tetrabromobenzene-1,3-disulfonamide [TBBDA], poly(N,N′-dibromo-N-ethylbenzene-1,3-disulfonamide) [PBBS] and a combination of TBBDA and nano-magnetic catalyst supported with functionalized 4-amino-pyridine silica (MNPs@SiO2-Pr-AP). The results showed that the use of TBBDA along with the MNPs@SiO2-Pr-AP gains the highest yields of the products in the shortest reaction time.An efficient protocol was developed for the one-pot synthesis of 2-amino-4-aryl thiazole derivatives via the reaction of substituted acetophenones and thiourea. The catalytic activity of three different types of catalytic systems was investigated in this reaction and it was demonstrated that the use of TBBDA along with the MNP@SiO2-Pr-AP under solvent-free conditions resulted in the highest yields of the products in the shortest reaction time.
      PubDate: 2017-10-30T03:21:16.414731-05:
      DOI: 10.1002/aoc.4127
       
  • Mesoporous chitosan-immobilized iron tetrakis(4-carboxyphenyl)porphyrin as
           a model of cytochrome P-450 enzyme for oxidation of ethylbenzene
    • Authors: Guan Huang; Tong-ming Su, Kai Zeng, Yong-an Guo, Shu-kai Zhao, Su-juan Wei
      Abstract: Mesoporous chitosan-grafted iron tetra (4-carboxyphenyl) porphyrin catalyst (Fe TCPP/mesp-CTS) was prepared and investigated as a practical model for the nano-cavity and coordinate regulation-catalysis(CRC) function in cytochrome P-450 enzyme. Fe TCPP/mesp-CTS was characterized by X-ray Diffraction(XRD), Thermogravimetry(TG), Ultraviolet–visible spectroscopy(UV-Vis), Ultraviolet–visible–Diffuse reflectance spectroscopy(UV-DRS), Scanning electron microscope (SEM), Fourier transform infrared spectroscopy(FT-IR), and X-ray photoelectron spectroscopy(XPS) techniques. The catalytic activity of Fe TCPP/mesp-CTS for ethylbenzene oxidation was investigated and it was proved to be a better catalyst than Fe TCPP/macp-CTS based on the ethylbenzene conversion, turnover numbers(TON), and the reusability. These results are attributed to the mesocavity and CRC of amino group in Fe TCPP/mesp-CTS. The highest ethylbenzene conversion and yields of ketone and alcohol were 24.4% and 18.2%, respectively.Mesoporous chitosan-immobilized iron tetrakis (4-carboxyphenyl) porphyrin as a model of cytochrome P450 enzyme was used for catalytic oxidation of ethylbenzene, providing with a good conversion and yield of K/A oil.
      PubDate: 2017-10-30T03:16:16.603847-05:
      DOI: 10.1002/aoc.4140
       
  • DNA/BSA binding interactions and VHPO mimicking potential of vanadium(IV)
           complexes: Synthesis, structural characterization and DFT studies
    • Authors: M.A. Neelakantan; Chithiraivel Balakrishnan, V. Selvarani, M. Theetharappan
      Abstract: Vanadium(IV) Schiff base complexes (VOL1-VOL3) were synthesized and characterized by elemental analysis, various spectral methods and single crystal XRD studies. Structural analysis of VOL2 reveals that the central vanadium ion in the complex is six coordinate with distorted octahedral geometry. Density functional theory (DFT) and time dependent (TD-DFT) studies were used to understand the electronic transitions observed in the complexes in UV–Vis spectra. The electrochemical behavior of the complexes was investigated in acetonitrile medium exhibit quasi-reversible one electron transfer. The DNA and BSA protein binding interaction of vanadium complexes has been explored by UV–Vis and fluorescence spectral methods and viscosity measurements reveal that the complexes interact with CT-DNA through intercalation mode and follows the order VOL1 
      PubDate: 2017-10-30T03:15:44.704236-05:
      DOI: 10.1002/aoc.4125
       
  • Arene chemistry: Reaction mechanisms and methods for aromatic compounds,
           Edited by Jacques Mortier Wiley, 2016; Hardcover £156.00, €187.20 992
           pages. ISBN: 978–1–118-75201-2
    • Authors: George Weaver
      PubDate: 2017-10-30T03:10:41.745482-05:
      DOI: 10.1002/aoc.4129
       
  • Co(II), Ni(II), Cu(II) and Zn(II) complexes of aminothiazole-derived
           Schiff base ligands: Synthesis, characterization, antibacterial and
           cytotoxicity evaluation, bovine serum albumin binding and density
           functional theory studies
    • Authors: A. Prakash; R. Malhotra
      Abstract: Transition metal complexes of type M(L)2(H2O)x were synthesized, where L is deprotonated Schiff base 2,4-dihalo-6-(substituted thiazol-2-ylimino)methylphenol derived from the condensation of aminothiazole or its derivatives with 2-hydroxy-3-halobenzaldehyde and M = Co2+, Ni2+, Cu2+ and Zn2+ (x = 0 for Cu2+ and Zn2+; x = 2 for Co2+ and Ni2+). The synthesized Schiff bases and their metal complexes were thoroughly characterized using infrared, 1H NMR, electronic and electron paramagnetic resonance spectroscopies, elemental analysis, molar conductance and magnetic susceptibility measurements, thermogravimetric analysis and scanning electron microscopy. The results reveal that the bidentate ligands form complexes having octahedral geometry around Co2+ and Ni2+ metal ions while the geometry around Cu2+ and Zn2+ metal ions is four-coordinated. The geometries of newly synthesized Schiff bases and their metal complexes were fully optimized in Gaussian 09 using 6–31 + g(d,p) basis set. Fluorescence quenching data reveal that Zn(II) and Cu(II) complexes bind more strongly to bovine serum albumin in comparison to Co(II) and Ni(II) complexes. The ligands and their complexes were evaluated for in vitro antibacterial activity against Escherichia coli ATCC 25922 (Gram negative) and Staphylococcus aureus ATCC 29213 (Gram positive) and cytotoxicity against lever hepatocellular cell line HepG2.Among the three ligands, HL3 exhibits maximum percentage inhibition as aminothiazole is sterically more demanding (R = R1 = H). Therefore a dose–response curve of ligand HL3 compared to standard drugs was obtained with concentration ranging from 30 to 0.2 μg ml−1.
      PubDate: 2017-10-30T03:10:40.090538-05:
      DOI: 10.1002/aoc.4098
       
  • BiOCl/UiO-66 composite with enhanced performance for photo-assisted
           degradation of dye from water
    • Authors: Xiaowen Tong; Zhiquan Yang, Jinna Feng, Ying Li, Hongguo Zhang
      Abstract: Semiconductor-based photocatalysis is an environmental friendly and cost-effective technique for water treatment. Due to their unique properties, metal–organic frameworks (MOFs) are considered as ideal platform to develop composite photocatalyst. In this study, Bismuth oxychloride (BiOCl) was first attempt to be incorporated with highly stable MOFs, UiO-66(Zr) by hydrothermal reaction. Different characterization methods including X-ray diffraction, Scanning electron microscopy, Fourier transform infrared spectroscope, X-ray photoelectron spectroscopy had been used to prove the successful synthesis of composite photocatalyst. The resultant BiOCl/UiO-66 composite showed higher photodegradation performance of Rhodamine B (RhB) under ultraviolet and visible light irradiation than that of pristine materials and their mechanically mixed sample. In addition, the composite exhibited good structural stability and reusability. The photocatalytic mechanism of RhB degradation over the composite under visible light proceeded via a photosensitization process. A better adsorptivity of RhB and effective electron transfer within the hybrid material might be responsible for the enhanced photocatalytic performance.BiOCl and UiO-66(Zr) were combined together through chemical bonds (C-Cl), and a different morphology compared to pristine material was obtained in the preparation process, which brought a better adsorptivity of RhB and effective electron transfer within the hybrid material. The BiOCl/UiO-66(Zr) composite shows prior photosensitization degradation performance for RhB under visible light than pristine materials.
      PubDate: 2017-10-30T03:07:45.59643-05:0
      DOI: 10.1002/aoc.4049
       
  • Iron promotion of V-HMS mesoporous catalysts for ultra-deep oxidative
           desulfurization
    • Authors: Shuzhi Liu; Fulin Zhao, Hongping Sun, Xianjun Liu, Baochen Cui
      Abstract: Bimetallic Fe-V-HMS (HMS, hexagonal mesoporous silica) catalysts with various molar ratios of iron to vanadium were synthesized using a co-synthesis method, and investigated for oxidative desulfurization of dibenzothiophene (DBT) using tert-butyl hydroperoxide as an oxidant. The catalysts were characterized using X-ray diffraction, temperature-programmed desorption of ammonia, Fourier transform infrared spectroscopy and N2 physical adsorption–desorption techniques. The Fe-V-HMS catalyst with a 2:1 molar ratio of iron to vanadium exhibited the highest total acidity and the highest catalytic activity. DBT was almost completely oxidized to dibenzothiophenesulfone, a species with a higher polarity that could be subsequently adsorbed on the Fe-V-HMS, and therefore the Fe-V-HMS acts as both a catalyst and an adsorbent simultaneously. The desulfurization rate was 98.1%. A pseudo-first-order model was fitted to the experimental data, and the activation energy was found to be 38.79 kJ mol−1. The encouraging performance of Fe-V-HMS offers the prospect of the design of a one-pot oxidative desulfurization process without needing extraction of sulfones from fuel oil with a chemical solvent.Bimetallic Fe-V-HMS catalyst was synthesized by the co-synthesis method. The catalyst acts as both a catalyst and an adsorbent simultaneously. DBT was almost completely oxidized to DBTO2 with a higher polarity over the catalyst using tertbutyl hydroperoxide (TBHP) in the absence of any co-solvent.
      PubDate: 2017-10-30T03:05:47.013132-05:
      DOI: 10.1002/aoc.4082
       
  • Dual-template crown ether-functionalized hierarchical porous silica:
           Preparation and application for adsorption of energy metal lithium
    • Authors: Xuechao Xu; Fengxian Qiu, Dongya Yang, Xudong Zheng, Yuanyuan Wang, Jianming Pan, Tao Zhang, Jicheng Xu, Chunxiang Li
      Abstract: Lithium is the lightest energy metal element on earth and it has applications in lithium batteries and nuclear fusion. With the development of high-tech and widespread applications of lithium, the demand for lithium continues to increase. In this work, a hierarchical porous lithium adsorbent (2M12C4-HPS) was synthesized from a precursor of hierarchical porous silica (HPS), the HPS being obtained via a dual-template technique. The microstructure and morphology of 2M12C4-HPS were characterized using scanning electron microscopy, transmission electron microscopy, X-ray diffraction and nitrogen adsorption–desorption measurements. The obtained hierarchical porous 2M12C4-HPS containing two kinds of pores with different sizes (peaking at about 2.01 and 7.82 nm) has a high specific surface area (1143.56 m2 g−1). Fourier transform infrared spectroscopy and thermogravimetric analysis were used to confirm the surface organic functional groups of 2M12C4-HPS, indicating that the functional group 2-methylol-12-crown-4 (2M12C4) was grafted on HPS successfully. The lithium adsorption properties, kinetics and isotherms of 2M12C4-HPS were investigated. The adsorption kinetics can be described by the pseudo-second-order kinetic model and the adsorption isotherms well fit the Langmuir isotherm equation. In addition, 2M12C4-HPS exhibited excellent specificity towards Li+. And the maximum adsorption rate of 2M12C4-HPS is up to about 94.34%. The obtained results indicate that 2M12C4-HPS has a broad commercial application prospect for adsorption of lithium.The highly efficient adsorption of energy metal lithium by a dual-template crown ether-functionalized hierarchical porous material (2M12C4-HPS) is reported.
      PubDate: 2017-10-30T03:03:54.92313-05:0
      DOI: 10.1002/aoc.4114
       
  • An efficient catalytic method for the synthesis of
           pyrido[2,3-d]pyrimidines as biologically drug candidates by using novel
           magnetic nanoparticles as a reusable catalyst
    • Authors: Saeid Moradi; Mohammad Ali Zolfigol, Mahmoud Zarei, Diego A. Alonso, Abbas Khoshnood, Aria Tajally
      Abstract: A convenient method for the synthesis of pyrido[2,3-d]pyrimidines by using the novel nano-magnetic silica-bonded S-sulfonic acid[Fe3O4@SiO2@(CH2)3S–SO3H] as an efficient and recyclable catalyst under neat conditions is described. The major advantages of the present methodology are high yield, short reaction time, and reusability of the catalyst. Furthermore, the nano-magnetic silica-bonded S-sulfonic acid was fully characterized by using various techniques such as FT-IR, TG/DTG, DTA, EDX, μXRF, XRD, HRTEM, SEM, SEM elemental mapping, XPS, and N2 physisorption. The results obtained from this research support the idea of rational design, synthesis, and applications of task-specific and reusable catalysts for the preparation of various polynitrogenated heterocyclic compounds containing 1,4-dihydropyridine moieties.A convenient method for the synthesis of pyrido[2,3-d]pyrimidines by using the novel nano-magnetic silica-bonded S-sulfonic acid[Fe3O4@SiO2@(CH2)3S–SO3H] as an efficient and recyclable catalyst under neat conditions is described. The major advantages of the present methodology are high yield, short reaction time, and reusability of the catalyst.
      PubDate: 2017-10-30T03:02:02.515257-05:
      DOI: 10.1002/aoc.4043
       
  • Ruthenium NNN complexes with a 2-hydroxypyridylmethylene fragment for
           transfer hydrogenation of ketones
    • Authors: Jing Shi; Shu Shang, Bowen Hu, Dafa Chen
      Abstract: Four NNN tridentate ligands L1–L4 containing 2-methoxypyridylmethene or 2-hydroxypyridylmethene fragment were synthesized and introduced to ruthenium centers. When (HOC5H3NCH2C5H3NC5H7N2) (L2) and (HOC5H3NCH2C5H3NC6H6N3) (L4) reacted with RuCl2(PPh3)3, two ruthenium chloride products Ru(L2)(PPh3)Cl2 (1) and Ru(L4)(PPh3)Cl2 (2) were isolated, respectively. Reactions of (MeOC5H3NCH2C5H3NC5H7N2) (L1) and (MeOC5H3NCH2C5H3NC6H6N3) (L3) with RuCl2(PPh3)3 in the presence of NH4PF6 generated two dicationic complexes [Ru(L1)2][PF6]2 (3) and [Ru(L3)2][PF6]2 (4), respectively. Complex 1 reacted with CO to afford product [Ru(L2)(PPh3)(CO)Cl][Cl]. The catalytic activity for transfer hydrogenation of ketones was investigated. Complex 1 showed the highest activity, with a turnover frequency value of 1.44 × 103 h−1 for acetophenone, while complexes 3 and 4 were not active.Several metal–ligand cooperative ruthenium complexes bearing NNN tridentate ligands show high activity for transfer hydrogenation of ketones.
      PubDate: 2017-10-30T02:50:41.016671-05:
      DOI: 10.1002/aoc.4100
       
  • Magnetically Recyclable Metal–Organic Framework@Fe3O4
           Composite-Catalyzed Facile Reduction of Nitroarene Compounds in Aqueous
           Medium
    • Authors: Sen Yang; Zhi-Hui Zhang, Qun Chen, Ming-Yang He, Liang Wang
      Abstract: A kind of Metal–organic framework (MOF) composite namely Cu-BTC@Fe3O4 (BTC = 1,3,5-benzenetricarboxylate) was prepared and showed good catalytic activity toward the reduction of nitroarenes. This reaction proceeded smoothly under mild reaction conditions in aqueous medium using sodium borohydride as the reduction agent, affording the corresponding anilines in good to excellent yields. In addition, the catalyst could be easily recovered with an external permanent magnet and be reused for successive six runs with slight decrease in its activity.A magnetically recyclable Cu-BTC@Fe3O4 composite was prepared and showed good catalytic activity toward the reduction of nitroarenes in aqueous medium.
      PubDate: 2017-10-30T02:45:53.982439-05:
      DOI: 10.1002/aoc.4132
       
  • Effect of ketene additive and Si/Al ratio on the reaction of methanol over
           HZSM-5 catalysts
    • Authors: Javad Hassanpour; Mehdi Zamani, Hossein A. Dabbagh
      Abstract: The influence of ketene as possible intermediate for the reaction of methanol to aromatics was investigated over HZSM-5 catalysts (Si/Al ratio of 15 and 9) using diketene-acetone (2,2,6-trimethyl-4H-1,3-dioxin-4-one) as ketene precursor under atmospheric pressure at 300 °C. The physicochemical properties of HZSM-5 catalysts were investigated by NH3-TPD, BET, XRD and ICP analysis. The distribution of products was measured by GC-Mass spectrometer. These catalysts exhibit high reactivity and selectivity for the conversion of methanol and/or ketene to hydrocarbons (mostly high octane number xylenes, trimethylbenzenes, tetramethylbenzenes and ≤1.5% benzene). The conversion of neat diketene-acetone over these catalysts produced aromatics compounds and significant amounts of oxygenated compounds (ketone, carboxylic acid, phenol, furan, pyran and others) depending on Si:Al ratio. These catalysts with high acid content produced small amount of saturated and unsaturated hydrocarbons without releasing significant amount of gas. The ketene and produced oxygenates from ketene appears to act as intermediates for the formation of aromatic compounds.The influence of ketene as possible intermediate for the reaction of methanol to aromatics was investigated over H-ZSM-5 catalysts (Si/Al ratio of 15 and 9) using diketene-acetone (2,2,6-trimethyl-4H-1,3-dioxin-4-one) as ketene precursor under atmospheric pressure at 300°C.
      PubDate: 2017-10-27T04:51:21.819043-05:
      DOI: 10.1002/aoc.4133
       
  • Issue Information
    • Abstract: No abstract is available for this article.
      PubDate: 2017-10-26T04:05:20.462092-05:
      DOI: 10.1002/aoc.3622
       
  • Cover Image
    • Authors: Salman Shojaei; Zarrin Ghasemi, Aziz Shahrisa
      Abstract: The cover image, by Salman Shojaei et al., is based on the Full Paper Cu(I)@Fe3O4 nanoparticles supported on imidazolium-based ionic liquid-grafted cellulose: Green and efficient nanocatalyst for multicomponent synthesis of N-sulfonylamidines and N-sulfonylacrylamidines,
      DOI : 10.1002/aoc.3788.
      PubDate: 2017-10-26T04:05:13.37943-05:0
       
  • Microporous assembly and shape control of a new Zn metal–organic
           framework: Morphology-dependent catalytic performance
    • Authors: Jiajia Wang; Yuqing Han, Haitao Xu, Zhen-Liang Xu
      Abstract: A new metal–organic framework (MOF), [Zn(ATA)(bpd)]∝ (1Zn) (ATA: 2-aminoterephthalic acid; bpd: 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene), exhibiting a three-dimensional extended porous structure was successfully assembled in a MeOH–H2O solvent system. Under various controlled conditions, 1Zn was obtained in a variety of morphologies such as microspheres, microblocks, microsheets, microplates and microrods. The catalytic performance of the 1Zn microsized MOF was evaluated, and a possible catalytic mechanism was proposed. The flexibility of this MOF assembly strategy for shape control will certainly enhance new potential applications of micro−/nano−MOFs.A multifunctional microporous metal–organic framework (1Zn) and its micro−/nanocrystals of various morphologies were successfully synthesized. 1Zn exhibited high catalytic activity in Knoevenagel condensation and degradation of methyl orange.
      PubDate: 2017-10-24T23:31:44.423553-05:
      DOI: 10.1002/aoc.4097
       
  • In vitro curcumin delivery and antibacterial activity of RuS2 and RuO2
           nanoparticles loaded chitosan biopolymer
    • Authors: Shadi Kheirandish; Mehrorang Ghaedi, Kheibar Dashtian, Faezeh Pourebrahim, Ramin Jannesar, Vahid Pezeshkpour
      Abstract: In this work, RuS2 and RuO2 nanoparticles loaded chitosan (Chitosan was extracted from Lobsters shells of Persian Gulf, IR. Iran) was prepared and characterized via FE-SEM, EDS and FT-IR analysis. FESEM showed the formation of spherical nanoparticles in size ranging of 20 to 100 mm. Subsequently, the role of these new materials as curcumin drug carrier and in vitro release of curcumin in simulated body fluid (SBF) solution (pH 7.4) were studied. RuS2-NPs-CS than to RuO2-NPs-CS showed higher drug loading efficiency (>91%) and rapid (
      PubDate: 2017-10-24T23:27:03.237808-05:
      DOI: 10.1002/aoc.4035
       
  • One-step in situ growth of magnesium ferrite nanorods on graphene and
           their microwave-absorbing properties
    • Authors: Wei Chen; Qingyun Liu, Xixi Zhu, Min Fu
      Abstract: The magnesium ferrite nanorods/graphene (MgFe2O4 NR/G) composites were prepared by a facile one-step surfactant-assisted solvothermal method. The structure and morphology of as-prepared composite materials were characterized by electron microscopy, energy dispersive spectrometry, Raman spectrometry, X-ray diffraction, FT-IR and X-ray photoelectron spectroscopy. The homogeneous MgFe2O4 nanorods with a typical diameter of about 100 nm were well distributed on graphene. The electromagnetic parameters were measured using a vector network analyzer. A minimum reflection loss (RL) of −40.3 dB was observed at 14.9 GHz with a thickness of 3 mm, and the effective absorption frequency (RL  
      PubDate: 2017-10-24T23:21:17.945212-05:
      DOI: 10.1002/aoc.4017
       
  • Catalytic application of sulfonic acid-functionalized titana-coated
           magnetic nanoparticles for the preparation of 1,8-dioxodecahydroacridines
           and 2,4,6-triarylpyridines via anomeric-based oxidation
    • Authors: Mohammad Ali Zolfigol; Fatemeh Karimi, Meysam Yarie, Morteza Torabi
      Abstract: We have developed green, efficient and powerful protocols for the preparation of 2,4,6-triarylpyridines and 1,8-dioxodecahydroacridines in the presence of Fe3O4@TiO2@O2PO2(CH2)2NHSO3H as a sulfonic acid-functionalized titana-coated magnetic nanoparticle catalyst under mild and solvent-free reaction conditions. These protocols furnished the desired products in short reaction times with good to high yields (20–40 min and 80–86% in the case of 2,4,6-triarylpyridines; 15–90 min and 80–93% in the case of 1,8-dioxodecahydroacridines). The final step of the mechanistic route in the synthesis of 2,4,6-triarylpyridines proceeds via an anomeric-based oxidation. Also, the nanomagnetic core–shell catalyst can be recycled and reused in both cases of the scrutinized one-pot multicomponent reactions with high turnover number and turnover frequency.Syntheses of 2,4,6-triarylpyridines and 1,8-dioxodecahydroacridines were carried out in the presence of a catalytic amount of Fe3O4@TiO2@O2PO2(CH2)2NHSO3H. The Triarylpyridines were prepared via an anomeric-based oxidation route.
      PubDate: 2017-10-24T23:20:49.595019-05:
      DOI: 10.1002/aoc.4063
       
  • Highly efficient Pd-PEPPSI-IPr catalyst for N-(4-pyridazinyl)-bridged
           bicyclic sulfonamides via Suzuki–Miyaura coupling reaction
    • Authors: Mallikarhuna Reddy Sura; N. Reddy Bijivemula, Sreekanth Reddy Pogula, Venkata Krishna Reddy Motakatla, Pathak Madhvesh, Vasu Govardhana Reddy Peddiahgari
      Abstract: A protocol for the Suzuki–Miyaura coupling of novel 2-(6-chloropyridazin-3-yl)-5-(aryl/heteroarylsulfonyl)-2,5-diazabicyclo[2.2.1]heptanes and heteroarylboronic acids to afford variety of coupled products was realized. Pd-PEPPSI-IPr catalyst was found to be a powerful and reusable catalyst under relatively mild reaction conditions.A protocol for the Suzuki–Miyaura coupling of novel 2-(6-chloropyridazin-3-yl)-5-(aryl/heteroarylsulfonyl)-2,5-diazabicyclo[2.2.1]heptanes and heteroarylboronic acids to afford variety of coupled products was realized. Pd-PEPPSI-IPr catalyst was found to be a powerful and reusable catalyst under relatively mild reaction conditions.
      PubDate: 2017-10-20T06:32:41.185255-05:
      DOI: 10.1002/aoc.4068
       
  • Chemically functionalized silica nanoparticles-based solid-phase
           extraction for effective pre-concentration of highly toxic metal ions from
           food and water samples
    • Authors: Maryam Rajabi; Mohtarameh Rahimi, Maryam Hemmati, Farhood Najafi
      Abstract: In this research study, an efficient solid-phase extraction procedure based on a new organometallic, effective, eco-friendly and bio-degradable nanoadsorbent was firstly introduced for influential pre-concentration of Cu(II), Zn(II), Pb(II), Cd(II) and Mn(II) ions from food and water samples followed by flame atomic absorption spectrophotometric determination. This safe adsorbent consisted of silica nanoparticles chemically functionalized with di-ethylen tri-amine (SiO2@NH2NPs); easily prepared via an effective and simple approach. Characterization of SiO2@NH2NPs was subsequently implemented via SEM, FT-IR and XRD; certifying high quality of the modified nanoadsorbent in terms of size, shape and surface functional groups. The effects of the main factors on the extraction efficiency were then optimized. Efficient extraction of the analytes of interest at neutral media accompanied with the aid of a bio-compatible organometallic nanoadsorbent can be considered as valuable advantages of the proposed approach. In the optimum conditions, calibration graphs were linear in the range of 4–700 μg l−1, with higher correlation coefficients than 0.997 and limits of detection of 1.45–4.10 ng ml−1. The enrichment factor values were found to be in the span of 120–400. The resultant extraction recovery values were satisfactory; possessing the proper relative standard deviation (%, n  =  5) values of 2.05–4.28%.In this research study, an efficient solid-phase extraction procedure based on a new organometallic, effective, eco-friendly and bio-degradable nanoadsorbent was firstly introduced for influential pre-concentration of Cu(II), Zn(II), Pb(II), Cd(II) and Mn(II) ions from food and water samples followed by flame atomic absorption spectrophotometric determination. This safe adsorbent consisted of silica nanoparticles chemically functionalized with di-ethylen tri-amine (SiO2@NH2NPs); easily prepared via an effective and simple approach.
      PubDate: 2017-10-19T03:41:01.919363-05:
      DOI: 10.1002/aoc.4012
       
  • Nanomagnetically modified vitamin B3 (Fe3O4@Niacin): An efficient and
           reusable green biocatalyst for microwave-assisted rapid synthesis of
           2-amino-3-cyanopyridines in aqueous medium
    • Authors: Mojgan Afradi; Sjjad Abbasi Pour, Maryam Dolat, Afshin Yazdani-Elah-Abadi
      Abstract: Superparamagnetic nanoparticles of modified vitamin B3 (Fe3O4@Niacin) represent a new, efficient and green biocatalyst for the one-pot synthesis of 2-amino-3-cyanopyridine derivatives via four-component condensation reaction between aldehydes, ketones, malononitrile, and ammonium acetate under microwave irradiation in water. This new magnetic organocatalyst was easily isolated from the reaction mixture by magnetic decantation using an external magnet and reused at least six times without significant degradation in the activity. The catalyst was fully characterized by FT-IR, XRD, SEM, VSM, UV–Vis, DLS and EDS. Excellent yield, very short reaction time (7–10 min), operational simplicity, easy work-up procedure, avoidance of hazardous or toxic catalysts and organic solvents are the main advantages of this green methodology which makes it more economic than the other conventional methods.Superparamagnetic nanoparticles of modified vitamin B3 (Fe3O4@Niacin) represent a new, efficient and green biocatalyst for the one-pot synthesis of 2-amino-3-cyanopyridine derivatives via four-component condensation reaction between aldehydes, ketones, malononitrile, and ammonium acetate under microwave irradiation in water. This new magnetic organocatalyst was easily isolated from the reaction mixture by magnetic decantation using an external magnet and reused at least six times without significant degradation in the activity. The catalyst was fully characterized by FT-IR, XRD, SEM, VSM, UV-Vis, DLS and EDS. Excellent yield, very short reaction time (7–10 min), operational simplicity, easy work-up procedure, avoidance of hazardous or toxic catalysts and organic solvents are the main advantages of this green methodology which makes it more economic than the other conventional methods.
      PubDate: 2017-10-19T03:37:14.879197-05:
      DOI: 10.1002/aoc.4103
       
  • Sustainable chitosan/starch composite material for stabilization of
           palladium nanoparticles: Synthesis, characterization and investigation of
           catalytic behaviour of Pd@chitosan/starch nanocomposite in
           Suzuki–Miyaura reaction
    • Authors: Talat Baran; Nuray Yılmaz Baran, Ayfer Menteş
      Abstract: We fabricated a green chitosan/starch composite as support material for stabilization of palladium nanoparticles for the first time. The chemical structure of the sustainable palladium nanocomposite was investigated using various techniques. Characterization studies showed that the average dimensions of the palladium nanocomposite ranged between 16 and 21 nm. The synthesized palladium nanocomposite was employed in the synthesis of a series of biphenyl compounds via Suzuki–Miyaura cross-coupling reactions with an unconventional technique. All coupling reactions were conducted in very short reaction time and excellent biphenyl yields were obtained in the presence of the nanocomposite. The palladium catalyst was tolerant to a wide range of functional groups. We also investigated the recyclability and reusability of the palladium nanocomposite, and found that it could be used for seven successive cycles.Synthesis of Pd(0) nanocatalyst immobilized on chitosan/starch composite.Average dimensions of Pd nanocomposite particles were found as 16–21 nm.Pd nanocomposite exhibited superior catalytic activity.The catalyst showed good reusability potential.
      PubDate: 2017-10-16T03:57:06.891761-05:
      DOI: 10.1002/aoc.4075
       
  • Electrochemical transformations and evaluation of antioxidant activity of
           some Schiff bases containing ferrocenyl and (thio-)phenol, catechol
           fragments
    • Authors: I.V. Smolyaninov; A.I. Poddel'sky, S.V. Baryshnikova, V.V. Kuzmin, E.O. Korchagina, M.V. Arsenyev, S.A. Smolyaninova, N.T. Berberova
      Abstract: Electrochemical transformations and antioxidant activity of some Schiff bases 1–5 containing ferrocenyl group and (thio-)phenol, catechol fragments were investigated. Compounds under investigation are: 2-(ferrocenylmethylene)amino)phenol (1), 2-((ferrocenylmethylene)amino)-4,6-di-tert-butylphenol (2), 2-((ferrocenylmethylene)amino)-thiophenol (3), 3-((ferrocenylmethylene)hydrazonomethyl)-4,6-di-tert-butylcatechol (4) and 2-((3,5-di-tert-butyl-4-hydroxybenzylidene)amino)thiophenol (5).In a case of compounds 1–3 it has shown that the sequence of electrochemical transformations leads to the products of intramolecular cyclization – 2-ferrocenylbenzoxazole (benzothiazole). o-Quinone formation occurs during the electrochemical oxidation of catechol-ferrocene 4 at the first anode stage. Electrochemical oxidation of the redox-active fragments in Schiff bases 1–4 can be achieved indirectly at a lower potential corresponding to the oxidation of ferrocenyl moiety, consequently these substances can reveal more pronounced antioxidant properties. The antioxidant activities of the compounds were evaluated using 2,2′-diphenyl-1-picrylhydrazyl radical (DPPH) assay, the reaction of 2,2′-azobis(2-amidinopropane hydrochloride) (AAPH) induced glutathione depletion (GSH), the oxidative damage of the DNA, the process of lipid peroxidation of rat (Wistar) brain homogenates in vitro. The compounds 1–4 in the antioxidant assays show effectiveness comparable with standard antioxidants (vitamin E, Trolox) and in some parameters superior to them. In the reaction of AAPH with the glutathione compounds 2–5 have a more pronounced protective activity than Trolox. Compounds 1–5 inhibit AAPH induced oxidation damage of the DNA. The more effective inhibitors of the lipid peroxidation process in vitro are molecules containing the bulky tert-butyl groups: 2 and 4 and Schiff base 3.Electrochemical oxidation of the redox-active fragments can be achieved indirectly at a low potential corresponding to the oxidation of ferrocenyl moiety. The Schiff bases can be activated at lower redox potentials and show pronounced antioxidant activity in comparison with the compounds containing phenolic or catecholic groups only.
      PubDate: 2017-10-16T03:47:33.954798-05:
      DOI: 10.1002/aoc.4121
       
  • New Ni(II), Pd(II) and Pt(II) complexes coordinated to azo pyrazolone
           ligand with a potent anti-tumor activity: Synthesis, characterization, DFT
           and DNA cleavage studies
    • Authors: Eman A. Bakr; Gad B. Al-Hefnawy, Mohamed K. Awad, Hossam H. Abd-Elatty, Mohamed S. Youssef
      Abstract: The absolute necessity to fight some class of tumor is perceived as serious health concerns, so the discovery and development of effective anticancer agents are urgently needed. (E)-4-((2-hydroxyphenyl)diazenyl)-3-phenyl-1H-pyrazol-5(4H)-one, HL, and its Ni(II), Pd(II) and Pt(II) complexes were synthesized and the biological activity was evaluated for antitumor, antioxidant and antimicrobial activity as well as DNA cleavage. Their structures were assigned depending on the elemental analysis, conductivity, magnetic moment, spectral measurements (IR, 1HNMR, mass and UV–Vis) and thermal analysis. 3D molecular modeling using DFT method confirmed that the geometrical structures agree well with the suggested experimental ones. The antitumor activity was evaluated against four different cell lines using MTT assay. The ligand HL showed a potent cytotoxic activity compared to 5-fluorouracil as a reference drug. For metal complexes, the order of activity was: Pd(II) > Ni(II) > Pt(II). A remarkable antioxidant activity for the ligand HL was recorded. It was higher than that of the metal complexes. Results of antimicrobial experiments revealed that all compounds were moderate to highly active against selected bacterial strains but inactive as antifungal except Pd(II) which showed a moderate antifungal activity. Gel electrophoresis showed insignificant nucleases activity for the ligand or its metal complexes even in the presence of H2O2 providing protection of DNA from damage. The antitumor activity of our compounds may be not due to DNA cleavage but may be referred to a mechanism similar to that of 5-fluorouracil which interfere with DNA replication. The present work suggests the use of this ligand in the design and development of new anticancer drugs.An aryl azo pyrazolone ligand HL, and its Ni(II), Pd(II) and Pt(II) complexes were synthesized, characterized and biologically screened as antitumor, antioxidant and antimicrobial agents. 3D molecular modeling using DFT method confirmed that the geometrical structures agree well with the suggested experimental ones. The ligand HL showed a potent cytotoxic activity higher than the metal complexes. Gel electrophoresis showed insignificant nucleases activity for the ligand or its metal complexes even in presence of H2O2 providing protection of DNA from damage.
      PubDate: 2017-10-16T03:46:01.364581-05:
      DOI: 10.1002/aoc.4104
       
  • Six-coordinated vanadium(IV) complexes with tridentate task-specific ionic
           liquid Schiff base ligands: Synthesis, characterization and effect of
           ionic nature on catalytic activity
    • Authors: Somayeh Azizi Talouki; Gholamhossein Grivani, Aliakbar Dehno Khalaji
      Abstract: By reaction of 5-(chloromethyl)salicylaldehyde with triphenylphosphine and N-methylimidazole in two separate reactions, salicylaldehydetriphenylphosphonium chloride (S2) and salicylaldehydemethylimidazolinium chloride (S3) were prepared. Reaction of 2-(aminomethyl)pyridine with these aldehydes resulted in the task-specific ionic liquid Schiff base ligands L1 and L2, respectively. Then six-coordinated vanadium(IV) Schiff base complexes of VO(acac)L1–4 were synthesized by reactions of these tridentate Schiff base ligands and VO(acac)2 in 1:1 stoichiometry. The aldehydes, ligands and VO(acac)L1–4 complexes were characterized using infrared, 1H NMR, 13C NMR, 31P NMR, UV–visible and mass spectroscopies, as well as elemental analysis. Paramagnetic property of the complexes was also studied using magnetic susceptibility measurements. The complexes were used as catalysts in epoxidation of cyclooctene and oxidation of methylphenyl sulfide and the reaction parameters were optimized. The effect of the ionic nature of the complexes was investigated in these oxidation reactions. The catalytic activity of the complexes could be varied by changing the ionic (cationic or anionic) character of VO(acac)L1–4 catalysts in which counter anion variation showed a greater effect than cationic moiety variation.By reaction of chlorosalicylaldehyde with triphenylphosphine and N-methylimidazole, salicylaldehydetriphenylphosphonium chloride (S2) and salicylaldehydemethylimidazolinium chloride (S3) were prepared. Reaction of 2-(aminomethyl)pyridine with these aldehydes resulted in task-specific ionic liquid Schiff base ligands L1 and L2. Then six-coordinated V(IV) Schiff base complexes of VO(acac)L1–4 were synthesized. The catalytic activity of these complexes was investigated; changing the ionic parts of them affected catalytic activity.
      PubDate: 2017-10-16T03:40:30.120463-05:
      DOI: 10.1002/aoc.4078
       
  • Novel water soluble bis(μ-chloro) bridged Cu(II) binuclear and
           mononuclear complexes: Synthesis, characterization and biological
           evaluation
    • Authors: Thangavel Thirunavukkarasu; H. Puschmann, H.A. Sparkes, Karuppannan Natarajan, V.G. Gnanasoundari
      Abstract: A water soluble chloro bridged binuclear copper(II) complex (3) and mononuclear complex (4) have been synthesized from chloro substituted 2-oxo-1,2-dihydroquinolin-3-yl-methylene-2 hydroxybenzohydrazide 1 and 2 and CuCl2·2H2O. The structures of the complexes have been determined by single crystal X-ray diffraction. The binding interactions of the ligands and complexes with CT-DNA and protein have been evaluated by absorption and emission spectroscopic method. CT-DNA and ethidium bromide (EB) competitive studies revealed that the compounds could interact with CT-DNA through intercalation binding mode. Interactions of the compounds with BSA were also studied by UV−visible, fluorescence and synchronous fluorescence spectroscopic methods which showed that the compounds had a strong binding affinity with BSA through static quenching process. The cytotoxic effect of the compounds examined on cancer cell lines, such as A549 (lung cancer) and MCF7 (breast cancer) cell lines showed that all four compounds exhibited substantial cytotoxic activity.A water soluble chloro bridged binuclear copper(II) complex (3) and mononuclear complex (4) have been synthesized from chloro substituted 2-oxo-1,2-dihydroquinolin-3-yl-methylene-2 hydroxybenzohydrazide 1 and 2 and CuCl2·2H2O. The structures of the complexes have been determined by single crystal X-ray diffraction. The binding interactions of the ligands and complexes with CT-DNA and protein have been evaluated by absorption and emission spectroscopic method.
      PubDate: 2017-10-16T03:40:02.750613-05:
      DOI: 10.1002/aoc.4111
       
  • HPA decorated Halloysite Nanoclay: An efficient catalyst for the green
           synthesis of Spirooxindole derivatives
    • Authors: Samahe Sadjadi; Majid M. Heravi, Masoumeh Malmir, Baharak Masoumi
      Abstract: A novel heterogeneous catalyst, HPA@HNTs-IMI-SO3H, was designed and synthesized based on functionalization of halloysite nanotubes with ionic liquid and subsequent incorporation of heteropolyacid. The structure of the catalyst was studied and confirmed by using SEM/EDX, FTIR, XRD, ICP-AES, TGA, DTGA and BET. Moreover, the catalytic activity of HPA@HNTs-IMI-SO3H was investigated for promoting ultrasonic-assisted three-component reaction of isatines, malononitrile or cyanoacetic esters and 1,3-dicarbonyl compounds to afford corresponding spirooxindole in high yields and short reaction time. The reusability of the catalyst was also studied. Notably, the catalyst could be recovered and reused for three reaction runs. However, reusing for fourth reaction runs led to the decrease of the catalytic activity. Considering leaching test results, that observation was attributed to the leaching of heteropolyacids, which can be induced by ultrasonic irradiation.Heteropolyacid was immobilized on ionic liquid-functionalized halloysite nanoclay to furnish a novel heterogeneous and reusable catalyst, HPA@HNTs-IMI-SO3H, for promoting ultrasonic-assisted three-component reaction of isatines, malononitrile or cyanoacetic esters and 1,3-dicarbonyl compounds to afford corresponding spirooxindole in high yields and short reaction time.
      PubDate: 2017-10-16T03:33:48.712855-05:
      DOI: 10.1002/aoc.4113
       
  • Supported ruthenium hydride catalysts for direct conversion of alcohols to
           carboxylic acids using styrene oxide as oxidant
    • Authors: Moloud Ghafouri; Majid Moghadam, Kheirollah Mehrani, Anahita Daneshvar
      Abstract: In the present work, the ability of two ruthenium hydride catalysts supported on multiwall carbon nanotubes, [Ru–H@EDT–MWCNT], and gold nanoparticles cored triazine dendrimer, [Ru–H@AuNPs–TD], in the direct conversion of alcohols to carboxylic acids via transfer hydrogenation using styrene oxide as oxidant is reported. Different alcohols were successfully converted to their corresponding carboxylic acids. The results showed that these two heterogeneous catalysts are more efficient than the homogeneous counterpart. In addition, the catalysts were reused several times.Two ruthenium hydride catalysts supported on multiwall carbon nanotubes, [Ru–H@EDT–MWCNT], and gold nanoparticles cored triazine dendrimer, [Ru–H@AuNPs–TD], were applied in the direct conversion of alcohols to carboxylic acids via transfer hydrogenation using styrene oxide as oxidant.
      PubDate: 2017-10-16T03:33:10.952418-05:
      DOI: 10.1002/aoc.4048
       
  • Cu(II) immobilized on mesoporous organosilica as an efficient and reusable
           
    • Authors: Zahra Nasresfahani; Mohammad Zaman Kassaee
      Abstract: Cu(II) immobilized on mesoporous organosilica nanoparticles (Cu2+@MSNs-(CO2−)2) has been synthesized, as a inorganic–organic nanohybrid catalyst, through a post-grafting approach. Its characterization is carried out by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Energy dispersive X-ray (EDX), Thermogravimetric/differential thermal analyses (TGA-DTA), and Nitrogen adsorption–desorption analysis. Cu2+@MSNs-(CO2−)2 exhibits high catalytic activity in the Biginelli reaction for the synthesis of a diverse range of 3, 4-dihydropyrimidin-2(1H)-ones, under mild conditions. The anchored Cu(II) could not leach out from the surface of the mesoporous catalyst during the reaction and it has been reused several times without appreciable loss in its catalytic activity.Preparation and catalytic activity of Cu2+@MSNs-(CO2−)2 in the Biginelli reaction for the synthesis of 3, 4-dihydropyrimidin-2(1H)-ones.
      PubDate: 2017-10-16T03:32:45.142151-05:
      DOI: 10.1002/aoc.4106
       
  • New anthracene based Schiff base ligands appended Cu(II) complexes:
           Theoretical study, DNA binding and cleavage activities
    • Authors: Ammavasai Gubendran; Gujuluva Gangatharan Vinoth Kumar, Mookkandi Palsamy Kesavan, Gurusamy Rajagopal, Periakaruppan Athappan, Jegathalaprathaban Rajesh
      Abstract: New anthracene based Schiff base ligands L1 and H(L2), their Cu(II) complexes [Cu(L1)Cl2] (1) and [Cu(L2)Cl] (2), (where L1 = N1,N2-bis(anthracene-9-methylene)benzene-1,2-diamine, L2 = (2Z,4E)-4-(2-(anthracen-9-ylmethyleneamino)phenylimino)pent-2-en-2-ol) have been prepared and characterized by elemental analysis, NMR, FAB-mass, EPR, FT-IR, UV–Vis and cyclic voltammetry. The electronic structures and geometrical parameters of complexes 1 and 2 were analyzed by the theoretical B3LYP/DFT method. The interaction of these complexes 1 and 2 with CT-DNA has been explored by using absorption, cyclic voltammetric and CD spectral studies. From the electronic absorption spectral studies, it was found that the DNA binding constants of complexes 1 and 2 are 8.7 × 103 and 7.0 × 104 M−1, respectively. From electrochemical studies, the ratio of DNA binding constants K+/K2+ for 2 has been estimated to be >1. The high binding constant values, K+/K2+ ratios more than unity and positive shift of voltammetric E1/2 value on titration with DNA for complex 2 suggest that they bind more avidly with DNA than complex 1. The inability to affect the conformational changes of DNA in the CD spectrum is the definite evidences of electrostatic binding by the complex 1. It can be assumed that it is the bulky anthracene unit which sterically inhibits these complexes 1 and 2 from intercalation and thereby remains in the groove or electrostatic. The complex 2 hardly cleaves supercoiled pUC18 plasmid DNA in the presence of hydrogen peroxide. The results suggest that complex 2 bind to DNA through minor groove binding.New Cu(II) complexes 1 and 2 of anthracene based Schiff base ligands. Characterization using various spectral and analytical tools. Geometrical parameters of Cu(II) complexes were analyzed by theoretical method. Complex 2 has effective DNA binding behavior than complex 1. Complex 2 comprises substantial DNA cleavage activity.
      PubDate: 2017-10-16T03:28:08.800083-05:
      DOI: 10.1002/aoc.4128
       
  • Pd-catalyzed Desulfitative reaction of Aryltrifluoroborates with sodium
           Arenesulfinates in water
    • Authors: Sheng Chang; Yong Bing Sun, Xiu Rong Zhang, Lin Lin Dong, He Yun Zhu, Hong Wei Lai, Dan Wang
      Abstract: An efficient procedure for the synthesis of biaryls was catalyzed by Pd(CH3CN)4(BF4)2 is reported. This Pd-catalyzed cross-coupling reaction of aryltrifluoroborates with sodium arenesulfinates was developed under mild and environmentally benign conditions, in water without any ligand or additive. The reaction gave a range of structurally diverse unsymmetrical bi-aryl molecules with excellent yields, in which the byproduct was sulfur dioxide. It is worth noting that this protocol is also applicable to many heterocyclic aromatics such as thiophene, furan, pyridine, quinoline, isoquinoline and indole.An efficient procedure for the synthesis of biaryls was catalyzed by Pd(CH3CN)4(BF4)2 is reported. This Pd-catalyzed cross-coupling reaction of aryltrifluoroborates with sodium arenesulfinates was developed under mild and environmentally benign conditions, in water without any ligand or additive. The reaction gave a range of structurally diverse unsymmetrical bi-aryl molecules including many heterocyclic aromatics with good yields, in which the byproduct was sulfur dioxide.
      PubDate: 2017-10-16T03:26:33.93373-05:0
      DOI: 10.1002/aoc.3970
       
  • HAp-encapsulated γ-Fe2O3-supported dual acidic heterogeneous catalyst for
           highly efficient one-pot synthesis of benzoxanthenones and
           3-pyranylindoles
    • Authors: Leila Kheirkhah; Manouchehr Mamaghani, Asieh Yahyazadeh, Nosrat Ollah Mahmoodi
      Abstract: A novel method is reported for the synthesis of benzoxanthenone and 3-pyranylindole derivatives via one-pot three-component reactions using a newly synthesized HAp-encapsulated γ-Fe2O3-supported dual acidic heterogeneous catalyst, as a reusable and highly efficient nanocatalyst. In this protocol the use of the nanocatalyst provided a green, useful and rapid method to generate products in short reaction times (4–20 min) and in excellent yields (87–96%). The paramagnetic nature of the catalyst provided a simple, trouble-free and facile approach for the separation of the catalyst by applying an external magnet, and it could be used in eight cycles without significant loss in catalytic efficiency.A novel method is reported for the synthesis of benzoxanthenone and 3-pyranylindole derivatives via one-pot three-component reactions using a newly synthesized HAp-encapsulated γ-Fe2O3-supported dual acidic nanocatalyst as a heterogeneous, reusable and highly efficient catalyst.
      PubDate: 2017-10-16T03:24:13.325505-05:
      DOI: 10.1002/aoc.4072
       
  • A versatile supported silver for heterogeneously catalysed processes:
           Synthesis of 3-Acyloxylindolines solvent-free conditions
    • Authors: Seyed Mohsen Sadeghzadeh; Rahele Zhiani, Shokufe Emrani, Fatemeh Abedi
      Abstract: We have found that fibrous nanosilica (KCC-1) can used as a excellent support for the synthesis of highly sparse nanoparticles and has high surface area that was functionalized with Tetrathia-azacyclopentadecane (TTACP) groups acting as the strong performers so that the Ag nanoparticles were well-dispersed without aggregation on the fibers of the KCC-1 microspheres (KCC-1/TTACP/Ag). We enthusiasm to report one-pot synthesis of 3-Acyloxylindolines for first time from N-tosyl-2-vinylaniline, and benzoic acid in the presence of KCC-1/TTACP/Ag as a catalyst.We have found that fibrous nanosilica (KCC-1) can used as a excellent support for the synthesis of highly sparse nanoparticles and has high surface area that was functionalized with Tetrathia-azacyclopentadecane (TTACP) groups acting as the strong performers so that the Ag nanoparticles were well-dispersed without aggregation on the fibers of the KCC-1 microspheres (KCC-1/TTACP/Ag). We enthusiasm to report one-pot synthesis of 3-Acyloxylindolines for first time from N-tosyl-2-vinylaniline, and benzoic acid in the presence of KCC-1/TTACP/Ag as a catalyst.
      PubDate: 2017-10-16T03:21:08.854193-05:
      DOI: 10.1002/aoc.4130
       
  • Immobilization of nickel ions onto the magnetic nanocomposite based on
           cross-linked melamine groups: Effective heterogeneous catalyst for
           N-Arylation of Arylboronic acids
    • Authors: Ali Pourjavadi; Nahid Keshavarzi, Firouz Matloubi Moghaddam, Seyed Hassan Hosseini
      Abstract: A new magnetic heterogeneous catalyst was synthesized by immobilization of nickel ions onto a cross-linked polymeric nanocomposite composed of cyanuric chloride, ethylenediamine and functionalized magnetic nanoparticles. The resulting nitrogen rich support was capable of adsorbing large amounts of nickel ions (1.20 mmol g−1). The synthesized catalyst was characterized using AAS, TEM, FT-IR, EDX, TGA, SEM, BET and XRD techniques. The performance of the prepared catalyst was investigated in the C-N coupling of arylamines with aryl boronic acids. The reaction was carried out under a mild condition and good to moderate to good yields of products was obtained using only 5.0 mol% of the catalyst. The catalyst was easily recovered and reused for at least 7 times without any significant loss of its activity.The robust synthesized catalysts based on poly melamine-like groups immobilized by nickel ions was used for N-arylation of arylboronic acids. The advantages of this catalyst are high loading level, great stability, magnetic recyclability and high product yields.
      PubDate: 2017-10-16T03:19:10.319224-05:
      DOI: 10.1002/aoc.4107
       
  • Cobalt(II)–metformin complexes containing α-diimine/α-diamine as
           auxiliary ligand: DNA binding properties
    • Authors: P. Vasantha; B. Sathish Kumar, B. Shekhar, P.V. Anantha Lakshmi
      Abstract: The cobalt(II) complexes [Co(Cl)2(met)(o-phen)] (1), [Co(Cl)2(en)(met)] (2) and [Co(Cl)2(met)(opda)] (3) (met = metformin, o-phen = ortho-phenanthroline, en = ethylenediamine, opda = ortho-phenylenediamine) were synthesized and characterized using liquid chromatography–mass spectrometry, elemental analysis, molar conductance measurements, thermal analysis, infrared spectroscopy, magnetic moment measurements, electronic spectroscopy and X-ray diffraction. The metal centre was found to be in an octahedral geometry. UV–visible absorption, fluorescence and viscosity measurements were conducted to assess the interaction of the complexes with calf thymus DNA. The complexes showed absorption hyperchromism in UV–visible spectra with DNA. The binding constants from UV–visible absorption studies were 1.38 × 105, 2.1 × 105 and 3.1 × 105 M−1 for 1, 2 and 3, respectively, and Stern–Volmer quenching constants from fluorescence studies were 0.146, 0.176 and 0.475, respectively. Viscosity measurements revealed that the binding of the complexes with DNA could be surface binding, mainly due to groove binding. The activities of the complexes in DNA cleavage decrease in the order 3 > 2 > 1. The complexes were docked into DNA topoisomerase II using Discovery Studio 2.1 software.DNA binding studies suggest that cobalt(II)–metformin complexes containing α-diimine/α-diamine as auxiliary ligands bind to DNA via groove binding.
      PubDate: 2017-10-16T03:18:47.930883-05:
      DOI: 10.1002/aoc.4074
       
  • Cu(II) immobilized on guanidinated epibromohydrin-functionalized
           γ-Fe2O3@TiO2 (γ-Fe2O3@TiO2-EG-Cu(II)): A highly efficient magnetically
           separable heterogeneous nanocatalyst for one-pot synthesis of highly
           substituted imidazoles
    • Authors: Mahdi Nejatianfar; Batool Akhlaghinia, Roya Jahanshahi
      Abstract: A simple, efficient and eco-friendly procedure has been developed using Cu(II) immobilized on guanidinated epibromohydrin-functionalized γ-Fe2O3@TiO2 (γ-Fe2O3@TiO2-EG-Cu(II)) for the synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazoles, via the condensation reactions of various aldehydes with benzil and ammonium acetate or ammonium acetate and amines, under solvent-free conditions. High-resolution transmission electron microscopy analysis of this catalyst clearly affirmed the formation of a γ-Fe2O3 core and a TiO2 shell, with mean sizes of about 10–20 and 5–10 nm, respectively. These data were in very good agreement with X-ray crystallographic measurements (13 and 7 nm). Moreover, magnetization measurements revealed that both γ-Fe2O3@TiO2 and γ-Fe2O3@TiO2-EG-Cu(II) had superparamagnetic behaviour with saturation magnetization of 23.79 and 22.12 emu g−1, respectively. γ-Fe2O3@TiO2-EG-Cu(II) was found to be a green and highly efficient nanocatalyst, which could be easily handled, recovered and reused several times without significant loss of its activity. The scope of the presented methodology is quite broad; a variety of aldehydes as well as amines have been shown to be viable substrates. A mechanism for the cyclocondensation reaction has also been proposed.A simple, efficient and eco-friendly procedure has been developed using γ-Fe2O3@TiO2-EG-Cu(II) for the synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazoles, via the condensation reactions of various aldehydes with benzil and ammonium acetate or ammonium acetate and amines, under solvent-free conditions. Fe2O3@TiO2-EG-Cu(II) was found to be a green and highly efficient nanocatalyst, which could be easily handled, recovered and reused several times without significant loss of activity.
      PubDate: 2017-10-16T03:16:18.570775-05:
      DOI: 10.1002/aoc.4095
       
  • Fabrication of nanoporous polymeric crystalline TiO2 composite for
           photocatalytic degradation of aqueous organic pollutants under visible
           light irradiation
    • Authors: Dasheng Gao; Ningning Liu, Weiwei Li, Yide Han
      Abstract: A nanoporous polymeric crystalline TiO2 composite (TiO2/PDVB-MA) has been successfully synthesized through an in situ synthesis method using divinylbenzene (DVB), methacrylic acid (MA) and tetrabutyl titanate. The experimental results showed that TiO2 nanoparticles composed of the mixture phases of anatase and rutile were homogeneously dispersed into the PDVB-MA support. The TiO2/PDVB-MA composite was used as photocatalyst for Rhodamine B (RhB), bisphenol A and 2,4,6-trichlorophenol degradation under visible light irradiation. More interestingly, the excellent photocatalytic performance of the composite was observed with regard to RhB and bisphenol A, which might be ascribed to the synergistic effect between TiO2 nanoparticles and PDVB-MA. Moreover, TiO2/PDVB-MA composite could be recycled at least four times in the removal of RhB, suggesting that it is a promising photocatalyst to catalyze the degradation of organic pollutants under visible light irradiation.A nanoporous polymeric crystalline TiO2 composite (TiO2/PDVB-MA) has been successfully synthesized through an in situ synthesis method using divinylbenzene, methacrylic acid and tetrabutyl titanate. The TiO2/PDVB-MA composite possesses excellent adsorptive performance and photocatalytic activity for organic pollutants degradation under visible light irradiation. This phenomenon is attributed to the rich porous structure of PDVB-MA support and the synergistic effect between TiO2 nanoparticles and support.
      PubDate: 2017-10-16T03:11:13.527891-05:
      DOI: 10.1002/aoc.4119
       
  • Heck and oxidative boron Heck reactions employing Pd(II) supported
           amphiphilized polyethyleneimine-functionalized MCM-41 (MCM-41@aPEI-Pd) as
           an efficient and recyclable nanocatalyst
    • Authors: Seyed Farshad Motevalizadeh; Masoumeh Alipour, Fatemeh Ashori, Alireza Samzadeh-Kermani, Hosein Hamadi, Mohammad Reza Ganjali, Hamideh Aghahosseini, Ali Ramazani, Mehdi Khoobi, Elham Gholibegloo
      Abstract: A novel nanocatalyst was developed based on covalent surface functionalization of MCM-41 with polyethyleneimine (PEI) using [3-(2,3-Epoxypropoxy)propyl] trimethoxysilane (EPO) as a cross-linker. Amine functional groups on the surface of MCM-41 were then conjugated with iodododecane to render an amphiphilic property to the catalyst. Palladium (II) was finally immobilized onto the MCM-41@PEI-dodecane and the resulted MCM-41@aPEI-Pd nanocatalyst was characterized by FT-IR, TEM, ICP-AES and XPS. Our designed nanocatalyst with a distinguished core-shell structure and Pd2+ ions as catalytic centers was explored as an efficient and recyclable catalyst for Heck and oxidative boron Heck coupling reactions. In Heck coupling reaction, the catalytic activity of MCM-41@aPEI-Pd in the presence of triethylamine as base led to very high yields and selectivity. Meanwhile, the MCM-41@aPEI-Pd as the first semi-heterogeneous palladium catalyst was examined in the C-4 regioselective arylation of coumarin via the direct C-H activation and the moderate to excellent yields were obtained toward different functional groups. Leaching test indicated the high stability of palladium on the surface of MCM-41@aPEI-Pd as it could be recycled for several runs without significant loss of its catalytic activity.Functionalizing the surfaces of MCM-41 with polyethylenimine (PEI) and [3-(2,3-epoxypropoxy)propyl]trimethoxysilane (EPO) and its amphiphilization by Iodododecane conjugation, then the adsorption of Pd inside its shell to produce MCM-41@aPEI-Pd, as an efficient, selective and stable nanocatalyst for the Heck and oxidative boron Heck reactions.
      PubDate: 2017-10-16T03:02:23.641966-05:
      DOI: 10.1002/aoc.4123
       
  • Synthesis and catalytic evaluation of Fe3O4/MWCNTs nanozyme as recyclable
           peroxidase mimetics: Biochemical and physicochemical characterization
    • Authors: Navvabeh Salarizadeh; Minoo Sadri, Reza H. Sajedi
      Abstract: In this research, the nanocomposite of multiwalled carbon nanotubes and magnetic metal oxide nanoparticles (Fe3O4/MWCNTs), as enzyme mimetic, was synthesized using an in situ chemical reduction method. The structure, composition and morphology of the prepared Fe3O4/MWCNT nanocomposite materials were characterized using X-ray diffraction, FT-IR and scanning electron microscopy with energy dispersive X-ray spectroscopy, respectively. The magnetic properties of the nanocomposite were investigated by the vibrating sample magnetometer. A colorimetric system involving nanozyme, phenol/4-aminoantipyrine and H2O2 was utilized for the determination of peroxidase mimetic catalytic assay. The obtained results confirmed that the synthesis of Fe3O4/MWCNTs nanostructures was successful. It was found that Fe3O4/MWCNTs nanohybrid exhibited peroxidase-like activity without any pH limitation. Colorimetric data demonstrated that the prepared nanocatalyst had higher catalytic activity toward H2O2 than MWCNTs. The kinetic parameters of the nanozyme, Km and Vmax, were estimated to be 8.3 mm and 1.4 mm min−1, respectively. The Fe3O4/MWCNTs nanostructures were also successfully applied for glucose detection. In addition, peroxidase-like activity of the nanozyme increased in the presence of butyl-imidazolium bromide ionic liquid. These biomimetic catalysts have some advantages, such as simplicity, stability, reusability and cost effectiveness, which makes them great candidates to be used in various fields of biotechnology applications.A magnetic nanozyme, Fe3O4/MWCNTs, as a peroxidase mimetics was fabricated using in situ chemical reduction method and characterized. Finally the peroxidase-like catalytic activity of nanocatalyst was investigated with the oxidation of peroxidase substrate, 4-aminoantipyrine (4-AAP)/phenol in the presence of H2O2 reagent to the pink colored quinoneimine product which provides a colorimetric detection of H2O2. Also, a combination of the peroxidase-like catalytic activity of the Fe3O4/MWCNTs nanozyme with glucose oxidase, allowed the system of a sensitive colorimetric assay for glucose monitoring.
      PubDate: 2017-10-16T03:01:58.664257-05:
      DOI: 10.1002/aoc.4018
       
  • Ferrocene-substituted bis(ethynyl)anthracene compounds as anticancer
           agents
    • Authors: Ajeet Singh; Pratibha Kumari, Abhinav Raghuvanshi, Shaikh M. Mobin, Pradeep Mathur
      Abstract: Three compounds (1–3) were synthesized, where ethynylferrocene is substituted at different positions of anthracene and anthraquinone, and their biological properties were investigated. Compounds 1–3 were characterized using NMR and mass spectroscopies and confirmed by their single-crystal X-ray structure. They were also characterized from electronic and photophysical properties. All three crystal structures were optimized using density functional theory calculations. The presence of C–H⋅⋅⋅π interactions in 1–3 leads to the formation of two- and three-dimensional networks. The bioactivity of 1–3 was expressed by molecular docking with various cancerous proteins, which participated in progression of cancer. Compound 2 displayed the best interaction with cancer-related Aurora A protein in terms of both binding energy (−10.61 kcal mol−1) as well as inhibition constant (16.74 nM). The molecular docking result also coincides with cytotoxicity on cancer cell lines (A375, HeLa) and DNA/protein binding affinity.The bioactivity of ethynylferrocene-based compound 2 led to the best interaction with cancer-related Aurora A protein in terms of both binding energy (−10.61 kcal mol−1) as well as inhibition constant (16.74 nM). The molecular docking result further coincides with cytotoxicity for cancer cell lines and DNA/protein binding affinity.
      PubDate: 2017-10-16T03:00:59.346695-05:
      DOI: 10.1002/aoc.4071
       
  • Effect of surface modification with various thiol compounds on colloidal
           stability of gold nanoparticles
    • Authors: Mahsa Mazloomi-Rezvani; Mehdi Salami-Kalajahi, Hossein Roghani-Mamaqani, Amin Pirayesh
      Abstract: Gold nanoparticles (AuNPs) are attractive materials due to their special optical and electronic properties. However, they tend to aggregate particularly in the presence of thiol-containing compounds. In this study, to investigate the effect of surface conjugation with thiol-containing compounds on colloidal stability, thiol compounds with various structures as modifying agents were used. To this end, AuNPs were synthesized and stabilized by trisodium citrate in aqueous solution, and then modified with thiol-containing compounds, namely cysteamine hydrochloride (MEA, containing primary amine groups), 2-mercaptoethanol (BME, containing hydroxyl groups), 1-dodecanthiol (LCA, containing long-chain alkyl groups) and thioglycolic acid (TGA, containing carboxylic acid groups). We studied the effect of thiol ligands on solution stability of colloidal AuNPs and on the formation of aggregates originating from the modification process using UV–visible spectroscopy, dynamic light scattering, field emission scanning electron microscopy and transmission electron microscopy. Results showed that surface modification with MEA, BME and LCA led to the formation of aggregates. However, conjugation with TGA showed a concentration-dependent behaviour: surface modification with low concentration resulted in the formation of aggregates whereas that with high concentration of TGA did not disturb the colloidal stability of AuNPs. Finally, the effect of surface modification on temperature increase of solutions originating from infrared light irradiation was studied, where the temperature increase depends on the surface-modifying compound.Colloidal AuNPs were conjugated with various thiol-containing compounds those had different functional groups. Colloidal stability of as-synthesized and modified nanoparticles were investigated in aqueous medium. Also, temperature rise of colloidal nanoparticles due to IR irradiation originated from SPR of nanoparticles were studied.
      PubDate: 2017-10-16T02:56:20.861844-05:
      DOI: 10.1002/aoc.4079
       
  • Synthesis and characterization of sodium polyaspartate-functionalized
           silica-coated magnetite nanoparticles: A heterogeneous, reusable and
           magnetically separable catalyst for the solvent-free synthesis of
           2-amino-4H-chromene derivatives
    • Authors: Akbar Mobinikhaledi; Hassan Moghanian, Masoumeh Ghanbari
      Abstract: An efficient and facile method was used for the synthesis of sodium polyaspartate-functionalized silica-coated magnetite nanoparticles. The structure of this nanoparticle was characterized by scanning electron microscopies, X-ray diffraction, energy-dispersive X-ray, Fourier transform infrared spectroscopies and vibrating sample magnetometry. Then, this compound was used as a reusable heterogeneous catalyst for green synthesis of 2-amino-4H-chromene derivatives via one-pot three-component reactions. This novel material showed great catalytic performance and the reactions which were carried out by this catalyst showed good to excellent yields. Besides, the catalyst could easily be separated from the reaction mixture by using an external magnetic field and it was stable enough to reuse several times without any significant reduction in the yield of reactions. Eco-friendliness, high purity of the desired products, short reaction time and easy workup procedure can be mentioned as the other advantages of this method.The synthesis of sodium polyaspartate-functionalized silica-coated magnetite nanoparticles and its efficient and application as a magnetically separable catalyst for green synthesis of 2-amino-4H-chromene derivatives via one-pot three-component reactions are reported.
      PubDate: 2017-10-16T02:50:38.885015-05:
      DOI: 10.1002/aoc.4108
       
  • Ligand-free Mizoroki–heck reaction using reusable modified graphene
           oxide-supported Pd(0) nanoparticles
    • Authors: Hojat Veisi; Najibeh Mirzaee
      Abstract: Palladium nanoparticles supported on graphene oxide surfaces modified with metformin was found to be an effective and recyclable nanocatalyst in Mizoroki–Heck coupling reactions under aerobic conditions without requiring any phosphine or ligand coordination. Excellent product yields were achieved with a wide variety of substrates and the catalyst could be recycled seven times without any noticeable loss of its catalytic activity.Palladium nanoparticles supported on graphene oxide surfaces modified with metformin was found to be an effective and recyclable nanocatalyst in Mizoroki–Heck coupling reactions.
      PubDate: 2017-10-16T02:41:39.818226-05:
      DOI: 10.1002/aoc.4067
       
  • Dodecatungstocobaltate heteropolyanion encapsulation into MIL-101(Cr)
           metal–organic framework scaffold provides a highly efficient
           heterogeneous catalyst for methanolysis of epoxides
    • Authors: Afsaneh Marandi; Shahram Tangestaninejad, Majid Moghadam, Valiollah Mirkhani, Adam Mechler, Iraj Mohammadpoor-Baltork, Farnaz Zadehahmadi
      Abstract: A heterogeneous catalyst was synthesized by encapsulation of a Keggin-type heteropolytungstate, potassium dodecatungstocobaltate trihydrate, K5[CoW12O40]·(Co-POM), into chromium(III) terephthalate (MIL-101). Encapsulation was achieved via a ‘build bottle around ship’ strategy in aqueous media, following a hydrothermal method. The structure of the resulting crystalline solid was characterized using X-ray diffraction, correlated with Fourier transform infrared and UV–visible spectroscopy. The metal content was analysed using optical emission spectroscopy. Transmission electron microscopy was used to measure particle size and N2 adsorption in a Brunauer–Emmett–Teller instrument to characterize the specific surface area. The catalytic activity was investigated using methanolysis of epoxides under mild conditions as a test reaction. The turnover frequency of the heterogeneous Co-POM@MIL-101 catalyst was more than 20 times higher than that of the homogeneous Co-POM catalyst. The Co-POM@MIL-101 catalyst was reused several times with negligible leaching of Co-POM and with no considerable loss of its initial efficiency. The simplicity of preparation, extraordinary stability and high reactivity make Co-POM@MIL-101 an exceptional catalytic matrix that is easily separable from reaction media.A heterogeneous catalyst was prepared using a one-pot procedure to encapsulate dodecatungstocobaltate heteropolyanion (Co-POM) into MIL-101(Cr) metal–organic framework. The resultant hybrid material, Co-POM@MIL-101, exhibited superior catalytic activity in the methanolysis of epoxides.
      PubDate: 2017-10-11T23:21:29.479765-05:
      DOI: 10.1002/aoc.4065
       
  • Regioselective lithiation of 1-benzylpyrazole derivatives: Synthesis of
           amides derived from pyrazole
    • Authors: Agnieszka Górska; Tomasz Kliś, Janusz Serwatowski
      Abstract: A series of brominated 1-benzylpyrazoles were deprotonated at the pyrazole 5-position or the benzylic position on treatment with lithium diisopropylamide in tetrahydrofuran at low temperature. The obtained organolithium intermediates were subjected to reaction with Me3SiCl, t-BuNCO, ClCONEt2 or ClCON(i-Pr)2 affording the respective silanes or amides after hydrolysis.A series of brominated 1-benzylpyrazoles were deprotonated at the pyrazole 5-position or at benzylic position on treatment with lithium diisopropylamide in tetrahydrofuran at low temperature. The obtained organolithium intermediates were subjected to reaction with Me3SiCl or t-BuNCO affording the respective silanes or amides after hydrolysis.
      PubDate: 2017-10-11T23:20:32.192881-05:
      DOI: 10.1002/aoc.4027
       
  • Spectroscopic studies, structural characterization and electrochemical
           studies of two cobalt (III) complexes with tridentate hydrazone Schiff
           base ligands: Evaluation of antibacterial activities, DNA-binding, BSA
           interaction and molecular docking
    • Authors: Roghayeh Fekri; Mehdi Salehi, Asadollah Asadi, Maciej Kubicki
      Abstract: Co(III) complexes of tridentate Schiff base ligands derived from N-(2-hydroxybenzylideneamino)benzamide (H2L1) and 2-(2-hydroxybenzylidene)hydrazine-1-carboxamide (H2L2) were synthesized and characterized using IR, Raman, 1H–NMR and UV–Vis spectroscopies. X-ray single crystal structures of complexes 1 and 2 have also been determined, and it was indicated that these Co(III) complexes are in a distorted octahedral geometry. The cyclic voltammetry (CV) of the complexes indicates an irreversible redox behavior for both complexes 1 and 2. The antibacterial effects of the synthesized compounds have been tested by minimum inhibitory concentration and minimum bactericidal concentration methods, which suggested that the metal complexes exhibit better antibacterial effects than the ligands against Gram-positive bacteria. The effects of the drug (drug  =  ligands and complexes) on bovine serum albumin (BSA) were examined using circular dichroism (CD) spectropolarimetry, and it was revealed that the BSA (BSA, as a carrier protein) secondary structure changed in the presence of the drug. Interaction of the drug with calf-thymus DNA (CT-DNA) was investigated by UV–Vis absorption, fluorescence emission, CV and CD spectroscopy. Binding constants were determined using UV–Vis absorption. The results indicated that the studied Schiff bases bind to DNA, with the hyperchromic effect and non-intercalative mode in which the metal complexes are more effective than ligands. Furthermore, molecular docking simulation was used to obtain the energetic and binding sites for the interaction of the complexes with Mycobacterium tuberculosis enoyl-acyl carrier protein reductase (InhA), and results showed that complex 1 has more binding energy.Co(III) complexes of tridentate Schiff base ligands derived from N-(2-hydroxybenzylideneamino)benzamide (H2L1) and 2-(2-hydroxybenzylidene)hydrazine-1-carboxamide (H2L2) were synthesized and characterized using IR, Raman, 1H NMR, and UV–Vis spectroscopies. X-ray single crystal structures of complexes 1 and 2 were also determined. Electrochemical properties of complexes 1 and 2 were investigated in acetonitrile. These compounds were tested for antibacterial activity against Gram-positive and Gram-negative bacteria. Also, the details of DNA-binding and BSA-binding of these compounds were reported. Finally, molecular docking studies were performed to illustrate the binding mode of the complexes.
      PubDate: 2017-10-11T08:10:43.869406-05:
      DOI: 10.1002/aoc.4019
       
  • Versatile cobalt complexes for initiating immortal ring-opening
           polymerization (ROP) of lactide (LA), mediating living radical
           polymerization of t-butyl acrylate (tBA) and catalyzing copolymerization
           of LA and tBA by combination of ROP and organometallic-mediated radical
           polymerization
    • Authors: Jianing Zhang; Baolong Wang, Liying Wang, Junmin Sun, Yongfeng Zhang, Zhenzhu Cao, Zhenqiang Wu
      Abstract: Low-cost, highly active and versatile amino-bis(phenolate) cobalt complexes are developed. The cobalt complexes can control living polymerization of different categories of monomers including lactide (LA) by immortal ring-opening polymerization in argon and even in air and acrylate via living radical polymerization (LRP). The cobalt-based catalysts were used for copolymerization of LA and acrylate. The immortal polymerization of LA using the cobalt complexes as initiators proceeds in argon and even in air and without the requirement for extensive drying techniques or inert atmosphere whilst retaining end-group fidelity. The cobalt complexes are used to mediate LRP of t-butyl acrylate (tBA) in methanol. The block copolymerization of LA and tBA catalyzed by single-site cobalt organometallic catalyst is also reported for the first time. This cobalt system offers a versatile and green way to produce homopolymers and block copolymers.Low-cost, highly active and versatile cobalt complexes can control immortal ring-opening polymerization (ROP) of lactide (LA), living radical polymerization of t-butyl acrylate (tBA) and unexpected copolymerization of LA and tBA by combination of ROP and organometallic-mediated radical polymerization (OMRP). The discovery of efficient, productive, nontoxic, versatile and inexpensive catalysts is a crucial requirement for sustainable growth of the green chemical industry.
      PubDate: 2017-10-11T08:10:33.172878-05:
      DOI: 10.1002/aoc.4077
       
  • Three-dimensional coordination polymers based on trimethyltin cation with
           nicotinic and isonicotinic acids as anticancer agents
    • Authors: Safaa El-din H. Etaiw; Tarek A. Fayed, Mohamed M. El-bendary, Hassan Marie
      Abstract: Two new coordination polymers, namely [Me3Sn(INA)] (CP1) and [Me3Sn(NA)] (CP2), where INA = isonicotinic acid and NA = nicotinic acid, were characterized using infrared, UV–visible and NMR spectroscopies, thermogravimetric analysis and single-crystal X-ray analyses. The structure of CP1 consists of a one-dimensional coordinated chain which is further extended creating a two-dimensional layer via hydrogen bonds. The two-dimensional layers propagate along the corresponding planes creating a three-dimensional framework by hydrogen bonding and edge-to-face π–π stacking. The asymmetric unit of CP2 contains one tin atom and one NA ligand exhibiting 1:1 stoichiometry. The structure of CP2 extends through coordination bonds to form a one-dimensional zigzag chain which further extends to create a three-dimensional network via crossing chains and hydrogen bonds. The tin atoms acquire distorted trigonal bipyramid (TBPY-5) geometry. CP1 and CP2 were designed to investigate their cytotoxic properties against various human cancer cell lines: hepatocellular carcinoma, mammary gland breast cancer, human prostate cancer and colorectal carcinoma. The compounds are good anticancer agents against the tested cell lines. Also they were screened for their antioxidant, anti-haemolytic, antibacterial and antifungal activities.The three-dimensional network structure of two new coordination polymers, [Me3Sn(INA)] (CP1) and [Me3Sn(NA)] (CP2), is developed by extensive hydrogen bonds and π–π stacking. CP1 and CP2 are good anticancer agents against various human cancer cell lines. They were screened for their antioxidant, anti-haemolytic, antibacterial and antifungal activities.
      PubDate: 2017-10-11T08:10:21.583962-05:
      DOI: 10.1002/aoc.4066
       
  • Fe3O4–cysteamine hydrochloride magnetic nanoparticles: New, efficient
           and recoverable nanocatalyst for Knoevenagel condensation reaction
    • Authors: Razieh Maleki; Eskandar Kolvari, Mehdi Salehi, Nadiya Koukabi
      Abstract: Fe3O4 magnetic nanoparticles (MNPs) were obtained using a reduction–precipitation method. These MNPs were modified with cysteamine hydrochloride. This catalyst was characterized using a number of physicochemical measurements. The Fe3O4–cysteamine MNPs, as an efficient and heterogeneous catalyst, were successfully used for Knoevenagel condensation under mild conditions. The activity of this nanomagnetic catalyst in the Knoevenagel condensation of aromatic aldehydes and malononitrile is described. Easy preparation of the catalyst, easy work-up procedure, excellent yields and short reaction times are some of the advantages.Fe3O4 magnetic nanoparticles (MNPs) were obtained by a reduction–precipitation method. These MNPs were modified with cysteamine hydrochloride. The resulting organic magnetic salt nanocatalyst was used in the Knoevenagel condensation of aromatic aldehydes and malononitrile or dimedone.
      PubDate: 2017-06-06T04:15:56.996611-05:
      DOI: 10.1002/aoc.3795
       
  • Synthesis, crystal structures, DNA/bovine serum albumin binding, DNA
           cleavage and cytotoxicity of five mononuclear zinc(II) complexes
    • Authors: Si-Tong Li; Zhong-Ying Ma, Xin Liu, Jin-Lei Tian, Shi-Ping Yan
      Abstract: Five new mononuclear zinc(II) complexes containing ligands with extended planar phenanthroline moieties (dipyrido-[3,2-a:2′,3′-c]phenazine (dppz) or dipyrido[3,2-d:2′,3′-f] quinoxaline (dpq)), namely [Zn(dppz)(acac)2]⋅CH3OH (1), [Zn(dppz)(dbm)(OAc)] (2), [Zn(dpq)(dbm) (OAc)] 1.5H2O (3), [Zn(dpq)(tfnb)(OAc)] (4) and [Zn(dpq)(tfnb)2] (5), where acac = acetylacetonate, tfnb = benzoyltrifluoroacetone and dbm = dibenzoylmethane, were synthesized and structurally characterized. The binding ability of complexes 1–5 with calf thymus DNA was investigated by spectroscopic titration methods and viscosity measurements. Results indicate that all complexes bind to calf thymus DNA via intercalative mode, and the DNA binding affinities of dppz complexes 1 and 2 are apparently stronger than those of dpq complexes 3–5. DNA photocleavage experiments reveal that these complexes are efficient DNA cleaving agents and they are more active in UV-A (365 nm) than in visible light. In particular, the in vitro cytotoxicity of the complexes for human cancer cell line A549 demonstrates that the five compounds have anticancer activity with low IC50 values. Meanwhile, interaction of the complexes with bovine serum albumin investigated using UV–visible and fluorescence methods indicates that all complexes can quench the intrinsic fluorescence of bovine serum albumin in a static quenching process.Five mononuclear zinc(II) complexes were synthesized and their binding modes to calf thymus DNA investigated using spectroscopic and viscosity measurements. These complexes have good activities as chemical nucleases and can quench the intrinsic fluorescence of bovine serum albumin in a static quenching process.
      PubDate: 2017-06-02T03:45:46.215879-05:
      DOI: 10.1002/aoc.3802
       
  • Ionic liquid-functionalized mesoporous silica nanoparticles
           ([pmim]FeCl4/MSNs): Efficient nanocatalyst for solvent-free synthesis of
           N,N′-diaryl-substituted formamidines
    • Authors: Zahra Nasresfahani; Mohammad Zaman Kassaee, Esmaiel Eidi
      Abstract: We report the synthesis of ionic liquid-functionalized mesoporous silica nanoparticles ([pmim]FeCl4/MSNs) via a method of post-grafting on parent MSNs. This hybrid material was characterized using scanning and transmission electron microscopies, energy-dispersive X-ray spectroscopy, nitrogen adsorption–desorption analysis, Fourier transform infrared spectroscopy, powder X-ray diffraction and thermal analyses. The material was utilized as an efficient heterogeneous catalyst for the synthesis of N,N′-diaryl-substituted formamidines through the reaction of triethyl orthoformate with arylamines under solvent-free conditions. The catalyst was recovered easily and reused several times without significant loss of its catalytic activity.The catalytic performance of nanoparticles ([pmim]FeCl4/MSNs) is confirmed for the synthesis of N,N′-diaryl-substituted formamidines through the reaction of triethyl orthoformate with arylamines.
      PubDate: 2017-05-16T02:55:40.228732-05:
      DOI: 10.1002/aoc.3800
       
  • Synthesis of Co(II), Cu(II), Hg(II), UO2(II) and Pb(II) binuclear
           nanometric complexes from multi-donor ligand: Spectral, modeling,
           quantitative structure–activity relationship, docking and antitumor
           studies
    • Authors: Jabir H. Al-Fahemi; Fawaz A. Saad, Nashwa M. El-Metwaly, Thoraya A. Farghaly, Marwa G. Elghalban, Kamel A. Saleh, Gamil A. Al-Hazmi
      Abstract: New synthesis of Co(II), Cu(II), Hg(II), UO2(II) and Pb(II) binuclear nanometric complexes derived from multi-donor ligand is reported. Structural and molecular formulae of all isolated complexes were established. Bi-negative hexa-dentate mode of ligand was proposed for the two central atoms in all complexes. Infrared, UV–visible, magnetic moments, electron paramagnetic resonance, thermogravimetric analysis and elemental analysis were used to build all structural formulae. X-ray diffraction and scanning electron microscopy were used to determine the morphological features of the compounds and to compute particle sizes. Theoretical computations were implemented to support the proposed formulae. Kinetic study was executed over suitable stages to clarify the comparative stabilities. The DFT/B3LYP method, using the Gaussian 09 program, was utilized for optimizing the distribution of atoms over all compounds except the UO22+ complex. This exclusion refers to an inability to find a suitable method. Significant parameters were estimated using frontier energies (highest occupied and lowest unoccupied molecular orbitals) and data log file. A quantitative structure–activity relationship study applying HyperChem was executed for the organic compound tautomer forms to give a significant view about their biological character. AutoDock tools 4.2 were used to investigate the biological trend of organic compounds (keto and enol) against three types of proteins. The types were chosen related to in vitro investigation: breast, prostate and liver carcinoma proteins. IC50 values indicated insignificant inhibition activity towards all carcinoma cell lines under investigation, except for the Hg(II) complex which displayed distinct activity against breast carcinoma compared with reference drug (doxorubicin).The bi-negative hexa-dentate ligand was proposed with all metal ions. Essential parameters were extracted to predict biological features for most stable stereo structures through molecular modeling and docking studies. A poor impact was recorded for the complexes against all three utilized carcinoma cell lines, except for the Hg(II) complex, which displayed a promising result against breast carcinoma
      PubDate: 2017-05-16T02:35:58.352595-05:
      DOI: 10.1002/aoc.3787
       
  • Synthesis and antimicrobial activity of bulky 3,5-di-tert-butyl
           substituent-containing silver–N-heterocyclic carbene complexes
    • Authors: Nazan Kaloğlu; İlknur Özdemir, Selami Günal, İsmail Özdemir
      Abstract: A series of novel benzimidazolium bromides containing bulky 3,5-di-tert-butyl group were synthesized in high yields as N-heterocyclic carbene (NHC) ligands. These NHC ligands were metallated with Ag2O under moderate conditions to give novel silver–NHC complexes. The structures of all compounds were characterized using 1H NMR, 13CNMR, infrared and elemental analysis techniques, which supported the proposed structures. The silver–NHC complexes were screened for their in vitro antimicrobial activities against the standard bacterial strains Enterococcus faecalis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa and the fungal strains Candida albicans and C. tropicalis. The results showed that most of the silver–NHC complexes inhibited the growth of all bacterial strains and fungal strains and were found to display effective antimicrobial activity against different microorganisms.Novel benzimidazolium bromides and their silver–NHC complexes were synthesized. These complexes were tested against Gram-negative bacteria (E. coli and P. aeruginosa), Gram-positive bacteria (E. faecalis and S. aureus) and fungi (C. albicans and C. tropicalis). The result showed that most of the silver–NHC complexes had good activities against the various microorganisms.
      PubDate: 2017-05-15T06:26:42.422327-05:
      DOI: 10.1002/aoc.3803
       
  • Chloroaluminate ionic liquid-modified silica-coated magnetic
           nanoparticles: Efficient and reusable catalyst for selective synthesis of
           mono- and bis-dihydropyrano[3,2-b]chromenediones
    • Authors: Ehsan Estakhri; Mahboobeh Nasr-Esfahani, Iraj Mohammadpoor-Baltork, Shahram Tangestaninejad, Majid Moghadam, Valiallah Mirkhani
      Abstract: The synthesis, characterization and catalytic activity of chloroaluminate ionic liquid-modified silica-coated magnetic nanoparticles ([SiPrPy]AlCl4@MNPs) are described. The prepared magnetic nanocatalyst was characterized using Fourier transform infrared spectroscopy, elemental analysis, vibrating sample magnetometry, scanning and transmission electron microscopies, X-ray diffraction and inductively coupled plasma analysis. The results showed that the ionic liquid had been successfully immobilized onto the magnetic support, and the resulting nanoparticles exhibited high catalytic activity for the synthesis of a diverse range of dihydropyrano[3,2-b]chromenediones via a one-pot, three-component and solvent-free reaction of aromatic aldehydes, 1,3-diones and kojic acid. This catalytic system also showed excellent activity in the selective synthesis of mono- and bis-dihydropyrano[3,2-b]chromenediones from dialdehydes. The procedure gave the products in excellent yields and in very short reaction times. Moreover, the catalyst could be reused eight times without loss of its catalytic activity.An efficient method is reported for the synthesis of substituted as well as mono- and bis-dihydropyrano[3,2-b]chromenediones in the presence of chloroaluminate ionic liquid-modified silica-coated magnetic nanoparticles ([SiPrPy]AlCl4@MNPs) as a reusable catalyst under solvent-free conditions.
      PubDate: 2017-05-05T00:45:35.731506-05:
      DOI: 10.1002/aoc.3799
       
  • AgPt nanoparticles supported on magnetic graphene oxide nanosheets for
           catalytic reduction of 4-nitrophenol: Studies of kinetics and mechanism
    • Authors: Mona Kohantorabi; Mohammad Reza Gholami
      Abstract: AgxPt100−x (x = 0, 25, 50, 75 and 100) nanoparticles were grown on the surface of magnetic graphene oxide nanosheets (Fe3O4@GO) for the first time. The as-prepared nanocomposites were characterized using various techniques such as Fourier transform infrared spectroscopy, powder X-ray diffraction, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, Brunauer–Emmett–Teller surface area analysis, vibrating sample magnetometry and thermogravimetric analysis. The Fe3O4@GO-AgxPt100−x catalysts were applied in the reduction of 4-nitrophenol (4-NP) to 4-aminophenol using sodium borohydride (NaBH4). The synthesized nanocomposites exhibited excellent catalytic performance in the reduction of 4-NP with high recyclability for five consecutive runs. The Fe3O4@GO-Ag75Pt25 nanocomposite exhibited the best catalytic activity with a rate constant as high as 140.6 × 10−3 s−1. The obtained kinetic data were modelled with the Langmuir–Hinshelwood equation. The energy of activation and thermodynamic parameters including enthalpy, entropy of activation and activation Gibbs free energy were calculated.AgPt nanoparticles were grown on the surface of magnetic graphene oxide nanosheets.Fe3O4@GO-AgxPt100−x catalysts showed excellent catalytic activity for reduction of 4-NP to 4-AP.Mechanism of reaction was studied, and thermodynamic parameters were calculated.
      PubDate: 2017-05-05T00:37:00.680126-05:
      DOI: 10.1002/aoc.3806
       
  • Copper immobilized on magnetite nanoparticles coated with ascorbic acid:
           An efficient and reusable catalyst for C─N and C─O cross-coupling
           reactions
    • Authors: Abdol R. Hajipour; Maryam Check, Zahra Khorsandi
      Abstract: In a continuation of using magnetic nanoparticle (MNP)-supported catalysts, ascorbic acid (readily available, very safe and with strong affinity to MNPs) was used instead of the commonly used silica layer coating. This hybrid was used for immobilizing copper nanoparticles to produce Cu/ascorbic acid@MNPs catalyst. The catalyst was characterized and used in carbon–oxygen and carbon–nitrogen (various substrates) cross-coupling reactions in aqueous media and at room temperature with excellent product yields. Furthermore, the catalyst could be quickly and completely recovered using an external magnetic field and reused for six reaction cycles without significant change in catalytic activity.Coating of magnetic Fe3O4 nanoparticles with ascorbic acid, as safe and available compound, was reported for the first time which used for immobilization of copper particles and prevention the MNPs aggregation. This new and efficient magnetic copper (I) nanocatalyst was employed in C-N and C-O coupling reactions in water and room temperature conditions.
      PubDate: 2017-04-27T12:37:21.575953-05:
      DOI: 10.1002/aoc.3769
       
  • Covalent supporting of novel dioxo-molybdenum tetradentate pyrrole-imine
           complex on Fe3O4 as high-efficiency nanocatalyst for selective epoxidation
           of olefins
    • Authors: Shadab Akbarpour; Abolfazl Bezaatpour, Elham Askarizadeh, Mandana Amiri
      Abstract: A novel Mo(VI) tetradentate Schiff base complex based on two pyrrole-imine donors was anchored covalently on Fe3O4 nanoparticles and characterized using physicochemical techniques. The catalytic epoxidation process was optimized in terms of the effects of solvent, reaction temperature, kind of oxidant and amount of oxidant and catalyst. Then the novel heterogeneous nanocatalyst was used for the efficient and selective catalytic epoxidation of internal alkenes (cyclohexene, cyclooctene, α-pinene, indene and trans-1,2-diphenylethene) and terminal alkenes (n-heptene, n-octene, n-dodecene and styrene) using tert-butyl hydroperoxide (70% in water) as oxidant in 1,2-dichloroethane as solvent. The prepared nanocatalyst is very effective for the selective epoxidation of cis-cyclooctene with 100% conversion, 100% selectivity and turnover frequency of 1098 h−1 in just 30 min. The magnetic nanocatalyst was easily recovered using an external magnetic field and was used subsequently at least six times without significant decrease in conversion.High-efficiency nanocatalyst for selective epoxidation of olefins with 100% conversion and 100% selectivity in 30 min. Novel dioxo-molybdenum tetradentate pyrrole-imine Schiff base complex. Synthesis of recoverable environmentally friendly catalyst system.
      PubDate: 2017-04-27T12:20:48.144725-05:
      DOI: 10.1002/aoc.3804
       
  • Facile synthesis of magnetic hybrid metal–organic frameworks with high
           adsorption capacity for methylene blue
    • Authors: Rui Wang; Chunhua Ge, Tianzhu Xing, Yuanyuan Zhang, Yundi Zhang, Xiangdong Zhang
      Abstract: A magnetic hybrid material (Fe3O4-COOH/HKUST-1) was easily synthesized via a two-step simple solvothermal method. Through adding sodium acrylate directly into the synthesis of Fe3O4 spheres, the surface has more carboxyl groups. It is notable that the reactions proceed without use of organic surfactants. The magnetic hybrid material was characterized using various techniques. The magnetic hybrid material has a high specific surface area (430.15 m2 g−1) and excellent magnetism (23.65 emu g−1). It is an efficient adsorbent for removing organic dyes like methylene blue (MB) from aqueous solution. It also can be easily recovered from liquid media using an external magnetic field. Adsorption experiment shows the magnetic hybrid material possesses a high adsorption capacity (118.6 mg g−1), and has high adsorption efficiency (94.3%) after five adsorption cycles with ethanol (0.2% HCl) as eluent. The sorption kinetics and isotherm analysis indicate these sorption processes are better fitted to the pseudo-second-order and Langmuir equations. Thermodynamic study shows the sorption processes are spontaneous and endothermic.A magnetic hybrid material (Fe3O4-COOH/HKUST-1) was easily synthesized via a two-step simple solvothermal method. The magnetic hybrid material has a high specific surface area and excellent magnetism and it is an efficient adsorbent for removing organic dyes like methylene blue (MB) from aqueous solution.
      PubDate: 2017-04-26T02:26:02.075397-05:
      DOI: 10.1002/aoc.3798
       
  • Palladium(II) complexes of aminothiazole-based phosphines: Synthesis,
           structural characterization, density functional theory calculations and
           catalytic application in heck reaction
    • Authors: Khodayar Gholivand; Mohammad Kahnouji, S. Mark Roe, Akram Gholami, Farzaneh T. Fadaei
      Abstract: Three Pd(II) complexes of some hemilabile ligands, aminothiazole-based phosphines, were synthesized to investigate the catalytic activity of them in Heck cross-coupling reactions. The crystal structures of complexes PdCl2[(Ph2P)HN(C3H2NS)] (C1) and PdCl2[(Ph2P)HN(C7H4NS)] (C3) were determined using X-ray crystallography, which reveals that the ligand coordinates in a chelating mode through P and N (endocyclic) atoms in square planar geometry. Experimental and theoretical studies (atoms in molecules and natural bond orbital analyses) show that the Pd(II) interacts more strongly with the P atom than the N atom in the chelated ligand, N^P. This trait can promote catalytic activity of the complexes in comparison with our previous work in which chelated ligands with two phosphorus atoms, P^P, were used. The influence of non-covalent intermolecular interactions on the assembly of the solid-state structures is also discussed in terms of geometrical analysis. The prepared complexes turn out to be useful pre-catalysts in Heck cross-coupling reactions owing to the coordinative flexibility of the hemilabile ligands. The protocol affords the corresponding products in greater yield than the same reactions with bis(phosphino)amine Pd(II) complexes, as the catalysts in our previous work.Synthesis of three Pd(II) complexes with some aminothiazole-based phosphines. Molecular structure and crystal packing of the complexes were investigated. They represent high catalytic activity in the Heck coupling reactions owing to the coordinative flexibility of the hemilabile ligand.
      PubDate: 2017-04-26T02:16:49.863736-05:
      DOI: 10.1002/aoc.3793
       
  • Immobilized polytriazole complexes of copper(I) onto graphene oxide as a
           recyclable nanocatalyst for synthesis of triazoles
    • Authors: Hossein Naeimi; Zahra Ansarian
      Abstract: An efficient solid-supported catalyst for the Huisgen [3 + 2] cycloaddition reaction between azides and alkynes was prepared from copper(I) iodide and 1,2,3-triazole-functionalized graphene oxide. This catalyst was then used for the efficient synthesis of β-hydroxy-1,2,3-triazoles giving access to these products in excellent yields. In this protocol, the catalyst was shown to have high activity, air-stability and recyclability. The formation of copper triazolide is very straightforward and energetically desirable. The catalyst can be isolated from copper-catalysed azide–alkyne cycloaddition reactions.A solid-supported catalyst for the Huisgen [3 + 2] cycloaddition reaction between azides and alkynes was prepared from copper(I) iodide and 1,2,3-triazole-functionalized graphene oxide. This catalyst was then used for the efficient synthesis of β-hydroxy-1,2,3-triazoles giving these products in excellent yields. The catalyst was shown to have high activity, air-stability and recyclability.
      PubDate: 2017-04-26T02:11:10.477778-05:
      DOI: 10.1002/aoc.3796
       
  • Chlorozincate(II) acidic ionic liquid: Efficient and biodegradable
           silylation catalyst
    • Authors: Faezeh Abbasi; Najmedin Azizi, Masumeh Abdoli-Senejani
      Abstract: A practical and highly efficient silylation of alcohol and phenol derivatives with hexamethyldisilazane (HMDS) using acidic ionic liquids under mild reaction conditions is described. A series of Brønsted as well as Brønsted–Lewis acidic ionic liquids were prepared and their performance investigated for the silylation of a wide variety of alcohols and phenols with HMDS. Imidazole- as well as N-methyl-2-pyrrolidone-based acidic ionic liquids have a higher catalytic activity for the protection of sensitive, hindered alcohols and phenols, thus providing an environmentally begin and versatile alternative to current acid catalysts. In addition, the acidic ionic liquids are reusable, being recovered easily and reused several times without significant deterioration in catalytic activity.A practical and highly efficient silylation of alcohol and phenol derivatives with hexamethyldisilazane (HMDS) using acidic ionic liquids (ILs) under mild reaction conditions is described. A series of Brønsted as well as Brønsted–Lewis acidic ILs were prepared and their performance investigated for silylation of a wide variety of alcohols and phenols with HMDS.
      PubDate: 2017-04-26T02:11:02.511932-05:
      DOI: 10.1002/aoc.3790
       
  • Synthesis of gold/polydopamine composite surfaces on glass substrates for
           localized surface plasmon resonance and catalysis
    • Authors: Jianying Yu; Shixiang Lu, Wenguo Xu, Ge He, Dongsheng He
      Abstract: Composite materials of polydopamine (PDA) and gold nanoparticles on glass substrates (Au/PDA@slide) were obtained via a simple chemical process. First, PDA films (PDA@slide) were formed by immersing slides in 20 mg ml−1 dopamine aqueous solution at pH = 8.5 for 1 h. Then, PDA@slide was dipped in 0.02 M chloroauric acid (HAuCl4) aqueous solution for a certain time, Au/PDA@slide being formed. Gold nanoparticles were obtained by the reductive properties of PDA. The morphology and chemical composition of the composite material were characterized using scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The catalytic properties of Au/PDA@slide were evaluated using the reduction of 4-nitrophenol (4-NP) in the presence of sodium borohydride (NaBH4) aqueous solution at room temperature. The catalytic activity of the optimal Au/PDA@slide was so satisfactory that the reduction of 4-NP was completed within 10 min. Moreover, the Au/PDA@slide composite material was stable up to five cycles without significant loss of its catalytic activity. In addition, Au/PDA@slide also exhibited photocatalytic ability, photodegrading 2.5 ml of 17.5 mg l−1 methyl orange in 100 min. By measuring the UV–visible absorption bands of Au/PDA@slide, it was proved that the condition of the strongest surface plasmon resonance of Au/PDA@slide was the optimal condition for catalytic reduction of 4-NP.Au/polydopamine (PDA) composite surfaces on glass substrates were prepared with PDA as both reducing and adhesion agent. This Au/PDA@slide exhibited high efficiency for the reduction of 4-nitrophenol and photodegradation of methyl orange.
      PubDate: 2017-04-20T04:23:20.94169-05:0
      DOI: 10.1002/aoc.3785
       
  • An acetatopalladium(II) complex with
           1-benzyl-N-(3,5-di-tert-butylsalicylidene)piperidin-4-amine: Synthesis,
           structure and catalytic applications in Suzuki–Miyaura coupling of
           arylboronic acids with hydroxyaryl halides
    • Authors: Srinivas Keesara; G. Narendra Babu, Samudranil Pal
      Abstract: The Schiff base 1-benzyl-N-(3,5-di-tert-butylsalicylidene)piperidin-4-amine (HL) and its acetatopalladium(II) complex having the formula [Pd(L)(OAc)] were synthesized. Both HL and [Pd(L)(OAc)] were characterized using elemental analysis and various spectroscopic (infrared, UV–visible, 1H NMR and 13C NMR) and mass spectrometric measurements. The molecular structure of the complex was determined using X-ray crystallographic analysis. In the complex, the pincer-like NNO-donor L− and the monodenate OAc− provide a distorted square-planar N2O2 coordination environment around the metal centre. The physicochemical properties and the spectroscopic features of [Pd(L)(OAc)] are consistent with its molecular structure. The complex was found to be an effective catalyst for the Suzuki–Miyaura cross-coupling reactions of hydroxyaryl halides with arylboronic acids in predominantly aqueous media. The reactions afforded hydroxybiaryl products in good to excellent yields with a wide substrate scope.Synthesis, X-ray structure and spectroscopic properties of a new palladium(II) complex of formula [Pd(L)(OAc)] (HL = 1-benzyl-N-(3,5-di-tert-butylsalicylidene)piperidin-4-amine) are described. The efficient catalytic activity of the complex in Suzuki–Miyaura cross-coupling reactions of hydroxyaryl halides with arylboronic acids in predominantly aqueous medium is demonstrated.
      PubDate: 2017-04-17T02:01:09.238864-05:
      DOI: 10.1002/aoc.3778
       
  • Highly reusable support-free copper(II) complex of
           para-hydroxy-substituted salen: Novel, efficient and versatile catalyst
           for C─N bond forming reactions
    • Authors: Hashem Sharghi; Mahdi Aberi, Pezhman Shiri
      Abstract: An air-stable, highly active and versatile method for C─N bond forming reactions is reported. Under mild conditions using a highly reusable support-free Cu(II)–salen complex, structurally diverse N-aryl-substituted compounds were obtained via direct C─N bond forming reaction of HN-heterocycles with aryl iodides or three-component C─N bond forming reaction of 2-bromobenzaldehyde, aniline derivatives and sodium azide in good to excellent yields. C─N bond forming reaction for benzimidazole derivatives was also performed in the presence of the catalyst under ambient conditions. A series of hybrid benzimidazoles bearing morpholine, tetrazole and quinoxaline backbones were produced using this method. All reactions were performed in short times under air. The Cu(II) catalyst could be reused up to eight times in the direct cross-coupling reaction of 9H–carbazole with iodobenzene without any decrease in its catalytic activity.Novel, efficient and versatile procedure for C─N bond forming reactions was developed. Under mild conditions using a highly reusable support-free Cu(II)-salen complex, structurally diverse N-aryl-substituted compounds were obtained. The catalyst can act as an efficient catalyst for synthesis of a series of hybrid benzimidazoles bearing morpholine, tetrazole and quinoxaline backbones, as well. The Cu(II) catalyst could be reused several times.
      PubDate: 2017-04-12T04:42:03.841127-05:
      DOI: 10.1002/aoc.3761
       
  • Synthesis, structure and electrocatalytic properties of a water-soluble
           copper complex supported by
           2-ethyl-2-(2-hydroxybenzylideneamino)propane-1,3-diol ligand
    • Authors: Dong Li; Ling-Zhi Tang, Yan Liu, Shu-Zhong Zhan
      Abstract: The reaction of 2-ethyl-2-(2-hydroxybenzylideneamino)propane-1,3-diol (H3L) with CuCl2⋅2H2O affords a new copper complex, [ClCu(H2L)], which has been determined using X-ray crystallography. In the solid, copper atom is four-coordinated by two oxygen atoms and one nitrogen atom from the ligand and one chlorine atom. Electrochemical studies show that the complex can act as an electrocatalyst for hydrogen evolution from a dimethylformamide solution of acetic acid and a neutral buffer (pH = 7.0) with a turnover frequency of 46.2 and 482 moles of hydrogen per mole of catalyst per hour at an overpotential of 941.6 and 837.6 mV, respectively.The reaction of 2-ethyl-2-(2-hydroxybenzylideneamino)propane-1,3-diol (H3L) with CuCl2⋅2H2O affords a new copper complex, [ClCu(H2L)], which has been determined by X-ray crystallography. This complex can act as an electrocatalyst for hydrogen generation both from acetic acid and aqueous buffer.
      PubDate: 2017-04-12T04:30:41.880149-05:
      DOI: 10.1002/aoc.3797
       
  • TiO2/nanoclinoptilolite as an efficient nanocatalyst in the synthesis of
           substituted 2-aminothiophenes
    • Authors: Farzad Javadi; Reza Tayebee, Bahram Bahramian
      Abstract: TiO2/nanoclinoptilolite (TiO2/NCP) was prepared by the mediation of hexadecyltrimethylammonium (HDTMA) as surfactant and used as an effective heterogeneous nanocatalyst for the preparation of substituted 2-aminotiophenes. The modified HDTMA/NCP was impregnated with titanium(IV) chloride solution followed by calcination at 500 °C for 20 h. The obtained nanocomposite was characterized using Fourier transform infrared spectroscopy, field emission scanning electron microscopy, inductively coupled plasma optical emission spectroscopy and X-ray diffraction. Moreover, the prepared nanocomposite had high stability and recoverability under mild and solvent-free conditions.TiO2/nanoclinoptilolite (TiO2/NCP) was prepared through impregnation of the NCP surface with titanium chloride solution, titanium ions being incorporated after calcination at 500 °C for 20 h. The manufactured nanocomposite showed good catalytic activity in the synthesis of 2-aminothiophene derivatives.
      PubDate: 2017-04-12T04:30:37.809436-05:
      DOI: 10.1002/aoc.3779
       
  • Synthesis, characterization and in vitro biological activity of new
           zinc(II) complexes of the nonsteroidal anti-inflammatory drug sulindac and
           nitrogen-donor ligands
    • Authors: Hijazi Abu Ali; Asia M. Shalash, Mutaz Akkawi, Suhair Jaber
      Abstract: Metal carboxylate compounds with nitrogen- and/or oxygen-donor ligands with various carboxylate coordination modes, monodentate, bidentate and bridging bidentate, have been shown to be important from biological and chemical aspects. Five zinc ion binary compounds, diaqua-bis-(2-((E)-5-fluoro-2-methyl-1-(4-(methylsulfinyl)benzylidene)-1H–inden-3-yl)acetato)zinc(II) (1), aqua-bis-(2-((E)-5-fluoro-2-methyl-1-(4-(methylsulfinyl)benzylidene)-1H–inden-3-yl)acetato)pyridin-2-aminezinc(II) (2), (2-((E)-5-fluoro-2-methyl-1-(4-(methylsulfinyl)benzylidene)-1H–inden-3-yl)acetato) pyridin-2-ylmethanaminezinc(II) (2-((E)-5-fluoro-2-methyl-1-(4-(methylsulfinyl)benzylidene)-1H–inden-3-yl)acetate) (3), bis-(2-((E)-5-fluoro-2-methyl-1-(4-(methylsulfinyl)benzylidene)-1H–inden-3-yl)acetato)-1,10-phenanthrolinezinc(II) (4) and bis-(2-((E)-5-fluoro-2-methyl-1-(4-(methylsulfinyl)benzylidene)-1H–inden-3-yl)acetato)-1,10-phenanthrolinezinc(II) (5), have been prepared and fully characterized. In addition, the complexes were evaluated for their antibacterial activity using the in vitro agar diffusion method against two Gram-positive (Staphylococcus epidermidis, Staphylococcus aureus) and two Gram-negative (Bordetella, Escherichia coli) bacteria and yeast species (Saccharomyces and Candida). Complex 5 showed reasonable activity against yeast. All compounds showed greater antibacterial activity against Gram-positive than Gram-negative bacteria. Results indicated that the efficiency of complex 5 in preventing the formation of β-hematin was 67.6%. The efficiency of chloroquine as a standard drug was reported as 93%. Furthermore, the phosphatase activity of the Zn(II) complexes was studied and results indicated an effect of the zinc complexes on phosphatase activity.Column diagram representing Semi-Quantitative test results of potential anti-malarial drug (complex 5): [Zn(2,9-dimephen)(sul)2] dissolved in DMSO, chloroquine (CQ) was used as positive control, while water and DMSO were used as negative controls, In this figure the absorption values of dissolved β-hematin (alkaline hematin) at 405 nm using ELISA reader were shown.
      PubDate: 2017-04-12T04:25:43.957962-05:
      DOI: 10.1002/aoc.3772
       
  • Cu(I)@Fe3O4 nanoparticles supported on imidazolium-based ionic
           liquid-grafted cellulose: Green and efficient nanocatalyst for
           multicomponent synthesis of N-sulfonylamidines and N-sulfonylacrylamidines
           
    • Authors: Salman Shojaei; Zarrin Ghasemi, Aziz Shahrisa
      Abstract: A novel heterogeneous nanocatalyst was fabricated by depositing copper iodide and Fe3O4 nanoparticles on imidazolium-based ionic liquid-grafted cellulose and successfully characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, powder X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, vibrating sample magnetometry and flame atomic absorption spectrometry. It was employed to catalyse the reaction of terminal acetylenes with sulfonyl azides to afford highly reactive sulfonyl ketenimine intermediates which were subsequently trapped by secondary amines to give N-sulfonylamidines and N-sulfonylacrylamidines under solvent-free conditions at room temperature. Good to excellent yields, very short reaction times, eco-friendly processing, easy separation and reusability without significant loss of catalytic activity were found to be the notable features of this synthetic protocol.1-Methyl-3-(oxiran-2-yl-methyl)-1H–imidazolium chloride was successfully bonded on the surface of Cellulose to subsequent loaded Fe3O4 and coordination by copper iodide as a novel nanocatalyst in the multicomponent synthesis of N-sulfonylamidines and N-sulfonylacrylamidines.
      PubDate: 2017-04-10T01:50:45.72611-05:0
      DOI: 10.1002/aoc.3788
       
  • A green synthesis of palladium nanoparticles by Sapindus mukorossi seed
           extract and use in efficient room temperature Suzuki–Miyaura
           cross-coupling reaction
    • Authors: Raju Kumar Borah; Abhijit Mahanta, Anurag Dutta, Utpal Bora, Ashim J. Thakur
      Abstract: A simple and green method for the synthesis of palladium nanoparticles using an aqueous extract of Sapindus mukorossi seed has been demonstrated. The synthesized nanoparticles were characterized using UV–visible spectroscopy, powxder X-ray diffraction, energy-dispersive X-ray analysis and transmission electron microscopy. The nanocatalyst was successfully utilized in an efficient Suzuki–Miyaura cross-coupling reaction at room temperature.A simple and green method for the synthesis of palladium nanoparticles using an aqueous extract of Sapindus mukorossi seed has been demonstrated. The synthesized nanoparticles were characterized using various methods. The nanocatalyst was successfully utilized in an efficient Suzuki–Miyaura cross-coupling reaction at room temperature.
      PubDate: 2017-04-10T01:46:52.759381-05:
      DOI: 10.1002/aoc.3784
       
  • Synthesis, characterization, density functional theory studies and
           antibacterial activity of a new Schiff base dioxomolybdenum(VI) complex
           with tryptophan as epoxidation catalyst
    • Authors: Zeinab Asgharpour; Faezeh Farzaneh, Mina Ghiasi, Mohammad Azarkish
      Abstract: A cis-dioxomolybdenum(VI) complex was prepared with MoO2(acac)2 and a Schiff base ligand (2-((2-hydroxybenzylidene)amino)-3-(1H-indol-3-yl)propanoic acid) derived from salicylaldehyde and l-tryptophan in ethanol and designated as [MoO2(Sal-Tryp)(EtOH)]. It was characterized using several techniques including thermogravimetric and elemental analyses and mass, Fourier transform infrared and UV–visible spectroscopies. Theoretical calculations were performed using density functional theory for studying the molecular structure. An in vitro antibacterial activity evaluation showed that [MoO2(Sal-Tryp)EtOH] complex exhibits good inhibitory effects against Gram-positive (Bacillus subtilis, Staphylococcus aureus) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria in comparison to standard antibacterial drugs. It was also found that [MoO2(Sal-Tryp)EtOH] complex successfully catalyses the epoxidation of cyclooctene, norbornene, cyclohexene, styrene, α-methylstyrene and trans-stilbene, with 45–100% conversions and 64–100% selectivities. Based on the obtained results, the heterogeneity and reusability of the catalyst seem promising.[MoO2(Sal-Tryp)EtOH] was prepared from Mo(acac)2 and a Schiff base ligand derived from salicylaldehyde and L-tryptophan. The prepared complex was found to successfully catalyze the epoxidation of some alkenes. The antibacterial activity of complex have also been evaluated.
      PubDate: 2017-04-10T01:40:46.170758-05:
      DOI: 10.1002/aoc.3782
       
  • Nanomagnetically modified thioglycolic acid (γ-Fe2O3@SiO2-SCH2CO2H):
           Efficient and reusable green catalyst for the one-pot domino synthesis of
           spiro[benzo[a]benzo[6,7]chromeno[2,3-c]phenazine] and
           benzo[a]benzo[6,7]chromeno[2,3-c]phenazines
    • Authors: Sajjad Abbasi Pour; Afshin Yazdani-Elah-Abadi, Mojgan Afradi
      Abstract: Superparamagnetic nanoparticles of modified thioglycolic acid (γ-Fe2O3@SiO2-SCH2CO2H) represent a new, efficient and green catalyst for the one-pot synthesis of novel spiro[benzo[a]benzo[6,7]chromeno[2,3-c]phenazine] derivatives via domino Knoevenagel–Michael–cyclization reaction of 2-hydroxynaphthalene-1,4-dione, benzene-1,2-diamines, ninhydrin and isatin. This novel magnetic organocatalyst was easily isolated from the reaction mixture by magnetic decantation using an external magnet and reused at least six times without significant loss in its activity. The catalyst was fully characterized using various techniques. This procedure was also applied successfully for the synthesis of benzo[a]benzo[6,7]chromeno[2,3-c]phenazines.Superparamagnetic nanoparticles of modified thioglycolic acid (γ-Fe2O3@SiO2-SCH2CO2H) represent a new, efficient and green catalyst for the one-pot synthesis of novel spiro[benzo[a]benzo[6,7]chromeno[2,3-c]phenazine] derivatives via domino Knoevenagel–Michael–cyclization reaction. This organocatalyst was easily isolated from the reaction mixture using an external magnet and reused at least six times without significant loss in activity. The catalyst was fully characterized. This procedure has also been applied successfully for the synthesis of benzo[a]benzo[6,7]chromeno[2,3-c]phenazines.
      PubDate: 2017-04-06T00:19:08.355973-05:
      DOI: 10.1002/aoc.3791
       
  • Role of Knoevenagel condensate pyrazolone derivative Schiff base ligated
           transition metal complexes in biological assay and cytotoxic efficacy
    • Authors: Rajakkani Paulpandiyan; Alagarraj Arunadevi, Natarajan Raman
      Abstract: A new bioessential Knoevenagel condensate Schiff base ligand (L) was synthesized by the reaction of 3-(4-hydroxy-3-methoxybenzyl)pentane-2,4-dione and 4-aminoantipyrine. The ligand forms monomeric divalent transition metal complexes (1–4) which were characterized using spectral and analytical data. All these complexes have the general formula [ML]Cl2, where M = Co(II), Ni(II), Cu(II) and Zn(II). They are electrolytic in nature and adopt square planar geometry. The binding propensity of these complexes with calf thymus DNA was investigated using absorption spectrophotometric titration, cyclic voltammetry and viscosity measurements. The binding constant values imply that the complexes bind with DNA via intercalation mode. The in vitro antibacterial and antifungal activities reveal that the complexes have good antimicrobial efficacy against a set of pathogens. The nucleolytic cleavage activity of these complexes on pUC18 DNA was investigated using agarose gel electrophoresis. Also, the in vitro cytotoxicity of the synthesized complexes against a panel of human tumour cell lines (MCF-7 and HeLa) and normal cell lines (NHDF and HEK) was assayed using the MTT method. Interestingly, complex 1 exhibits more potent anticancer activity than cisplatin and other complexes.A new series of Knoevenagel condensate Schiff base metal(II) complexes have been synthesized and characterized using spectral and analytical data. They act as strong intercalators, are potential chemical nucleases and show good antimicrobial performance. The complexes show substantial cytotoxic activity towards tumour cell lines. All investigations reveal that the Cu(II) complex has a useful biological profile.
      PubDate: 2017-04-06T00:18:48.058073-05:
      DOI: 10.1002/aoc.3792
       
  • Synthesis of N,N′,X-tridentate 2-iminomethylpyrrole-coordinated
           palladium(II) complexes via N─H bond activation of pyrrole moiety
    • Authors: Dongil Kim; Jaeyoung Seo, Saira Nayab, Hyosun Lee
      Abstract: The reaction of [Pd(CH3CN)2Cl2] with N-functional group-substituted 2-iminomethylpyrrole-based ligands, namely N1-((1H-pyrrol-2-yl)methylene)-N3,N3-dimethylpropane-1,3-diamine (LA), N1-((1H-pyrrol-2-yl)methylene)-N3-methyl-N3-phenylpropane-1,3-diamine (LB), N-((1H-pyrrol-2-yl)methylene)-3-(methylthio)propan-1-amine (LC) and N-((1H-pyrrol-2-yl)methylene)-3-methoxypropan-1-amine (LD), resulted in [LnPdCl] (Ln = LA–LD) complexes in high yield via N─H bond activation of pyrrole moiety without use of base. [LnPdCl] existed as monomeric four-coordinated complexes with slightly distorted square planar geometries around the palladium metal center. The ligands show N,N′,X-tridentate binding mode to the palladium metal center to give two fused ring metallacycles. [LBPdCl] gave the highest activity (3.29 × 105 g PMMA (mol Pd)−1 h−1) for a methyl methacrylate (MMA) polymerization in the presence of modified methylaluminoxane at 60 °C compared to the other Pd(II) analogues, and resulted in PMMA with higher molecular weight (Mw = 7.16 × 105 g mol−1) and narrower polydispersity index. Syndiotactic-enriched PMMA resulted in all cases.Novel Pd(II) complexes supported by N,N′,X-tridentate ligands containing 2-iminomethylpyrrole have been synthesized via N─H bond activation of pyrrole moiety without presence of base. The structures were monomeric with Pd(II) atoms in distorted square planar geometries. [LBPdCl] showed the highest catalytic activity among the complexes for MAA polymerization, affording high-molecular-weight PMMA. Steric encumbrance in the ligand framework around the metal center exerted considerable influence on activity and stereoselectivity of the corresponding complexes leading to the production of syndio-enriched PMMA.
      PubDate: 2017-04-05T01:30:57.683459-05:
      DOI: 10.1002/aoc.3780
       
  • Magnetic d-penicillamine-functionalized cellulose as a new heterogeneous
           
    • Authors: Sajjad Keshipour; Kamran Adak
      Abstract: A new efficient heterogeneous catalyst is introduced for the oxidation of ethylbenzene. The catalyst was obtained in three steps: functionalization of cellulose with d-penicillamine, deposition of Fe3O4 nanoparticles on cellulose–d-penicillamine and then anchoring of Co(II) to the magnetic cellulose–d-penicillamine. High yield and excellent selectivity were achieved for the oxidation of ethylbenzene to acetophenone in ethanol under reflux conditions using H2O2 as a green oxidant. Also, the recovered catalyst could be applied six times without a decrease in activity.An efficient heterogeneous catalyst is introduced for the oxidation of ethylbenzene. The catalyst was obtained in three steps: functionalization of cellulose with d-penicillamine, deposition of Fe3O4 nanoparticles on cellulose–d-penicillamine and then anchoring of Co(II) to magnetic cellulose–d-penicillamine. High yield and excellent selectivity were achieved for the oxidation of ethylbenzene to acetophenone in EtOH at reflux using H2O2 as a green oxidant. The recovered catalyst can be applied six times without decrease in activity.
      PubDate: 2017-04-04T02:05:51.191993-05:
      DOI: 10.1002/aoc.3774
       
  • Preparation, characterization, biological activity, density functional
           theory calculations and molecular docking of chelates of diazo ligand
           derived from m-phenylenediamine and p-chlorophenol
    • Authors: Walaa H. Mahmoud; Gehad G. Mohamed, Ahmed M. Refat
      Abstract: A novel azo dye ligand, 2,2′-(1,3-phenylenebis(diazene-2,1-diyl))bis(4-chlorophenol), was synthesized from the diazotization of m-phenelyenediamine and coupling with p-chlorophenol in alkaline medium. Mononuclear Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes of the azo ligand (H2L) were prepared and characterized using elemental analyses, infrared spectroscopy, electron spin resonance, magnetic susceptibility, conductance measurements and thermal analyses. The UV–visible, 1H NMR and mass spectra of the ligand and its chelates were also recorded. The analytical data showed that the metal-to-ligand ratio in the mononuclear azo complexes was 1:1. Diffuse reflectance and magnetic moment measurements revealed the complexes to have octahedral geometry. The infrared spectral data showed that the chelation behaviour of the ligand towards transition metal ions was through phenolic oxygen and azo nitrogen atoms. The electronic spectral results indicated the existence of π  π* (phenyl rings) and n  π* (─N═N) and confirmed the mentioned structure. Molar conductivity revealed the non-electrolytic nature of all chelates. The presence of water molecules in all complexes was supported by thermal studies. Molecular docking was used to predict the binding between H2L and the receptors of breast cancer mutant 3hb5-oxidoreductase, crystal structure of Escherichia coli (3 t88) and crystal structure of Staphylococcus aureus (3q8u). The molecular and electronic structure of H2L was optimized theoretically and the quantum chemical parameters were calculated. In addition, the effects of the H2L azo ligand and its complexes on the inhibition of bacterial or fungal growth were evaluated. The prepared complexes had enhanced activity against bacterial or fungal growth compared to the H2L azo ligand.Mononuclear complexes of the prepared azo ligand with different transition metal ions were synthesized.The nature of bonding of the complexes deduced from elemental analyses, spectral studies, conductivity measurements, thermogravimetric analyses and further confirmed by X-ray powder diffraction, also the quantum chemical parameters were calculated.The antimicrobial data reveals that azo ligand show inhibition capacity less than the corresponding complexes against all the species under study, in addition to molecular docking with different proteins was performed.
      PubDate: 2017-04-04T01:55:40.732243-05:
      DOI: 10.1002/aoc.3753
       
  • Novel nano molten salt tetra-2,3-pyridiniumporphyrazinato-oxo-vanadium
           tricyanomethanide as a vanadium surface-free phthalocyanine catalyst:
           Application to Strecker synthesis of α-aminonitrile derivatives
    • Authors: Saeed Baghery; Mohammad Ali Zolfigol, Maliheh Safaiee, Diego A. Alonso, Abbas Khoshnood
      Abstract: Efficient and recyclable novel nano tetra-2,3-pyridiniumporphyrazinato-oxo-vanadium tricyanomethanide, {[VO(TPPA)][C(CN)3]4}, as a vanadium surface-free phthalocyanine-based molten salt catalyst was successfully designed, produced and used for the Strecker synthesis of α-aminonitrile derivatives through a one-pot three-component reaction between aromatic aldehydes, trimethylsilyl cyanide and aniline derivatives under neat conditions at 50 °C. This catalyst was well characterized using Fourier transform infrared, UV–visible, X-ray photoelectron and energy-dispersive X-ray spectroscopies, X-ray diffraction, scanning and high-resolution transmission electron microscopies, inductively coupled plasma mass spectrometry and thermogravimetric analysis. The catalyst can be simply recovered and reused several times without significant loss of catalytic activity.High yields of α-aminonitrile derivatives can be attained via Strecker synthesis in the presence of novel nano tetra-2,3-pyridinoporphyrazinato-oxo-vanadium tricyanomethanide, {[VO(TPPA)][C(CN)3]4}, as a vanadium surface-free phthalocyanine-based molten salt catalyst.
      PubDate: 2017-03-30T04:32:19.76798-05:0
      DOI: 10.1002/aoc.3775
       
  • Orthopalladated complexes of phosphorus ylide:
           Poly(N-vinyl-2-pyrrolidone)-stabilized palladium nanoparticles as reusable
           heterogeneous catalyst for Suzuki and Heck cross-coupling reactions
    • Authors: Kazem Karami; Sedigheh Abedanzadeh, Omolbanin Vahidnia, Pablo Herves, Janusz Lipkowski, Krzysztof Lyczko
      Abstract: The phosphorus ylide [Ph3PCHC(O)C6H4-NO2–4] reacted with Pd(OAc)2 to give the C,C-orthometallated complex [Pd{κ2(C,C)-C6H4PPh2C(H)CO(C6H4-NO2–4)}(μ-OAc)]2, which underwent bridge exchange reaction with NaN3, NaCl, KBr and KI, respectively, to afford the binuclear C,C-orthopalladated complexes [Pd{κ2(C,C)-C6H4PPh2C(H)CO(C6H4-NO2–4)}(μ-X)]2 (X = N3 (1), Cl (2), Br (3) and I (4)). The complexes were identified using spectroscopy (infrared and NMR), CHNS technique and single-crystal X-ray structure analysis. Thereafter, palladium nanoparticles with narrow size distribution were easily prepared using the refluxing reaction of iodo-bridged orthopalladated complex 4 with poly(N-vinyl-2-pyrrolidone) (PVP) as the protecting group. The PVP-stabilized palladium nanoparticles were characterized using a variety of techniques including X-ray diffraction, transmission and scanning electron microscopies, energy-dispersive X-ray spectroscopy, inductively coupled plasma analysis and Fourier transform infrared spectroscopy. The catalytic activity of the PVP-stabilized palladium nanoparticles was evaluated in the Suzuki reaction of phenylboronic acid and the Heck reaction of styrene with aryl halides of varying electron densities. This catalyst exhibited excellent catalytic activity for Suzuki cross-coupling reactions in ethanol–water. Notably, aryl chlorides which are cheaper and more accessible than their bromide and iodide counterparts also reacted satisfactorily using this catalyst. After completion of reactions, the catalyst could be separated using a simple method and used many times in repeat cycles without considerable loss in its activity.Synthesis, characterization and catalytic activity of the iodo-bridge orthopalladated complex, stabilized with poly(N-vinyl-2-pyrrolidone) (PVP), was investigated in the Suzuki reaction of phenylboronic acid and the Heck reaction of styrene with aryl halides of varying electron densities. This catalyst exhibited excellent catalytic activity and reusability in repeating cycles without considerable loss of activity.
      PubDate: 2017-03-30T04:31:36.901698-05:
      DOI: 10.1002/aoc.3768
       
  • Novel cytotoxic oxovanadium(IV) complexes: Influence of
           
    • Authors: Sanjay B. Gajera; Jugal V. Mehta, Darshana N. Kanthecha, Ravi R. Patel, Mohan N. Patel
      Abstract: Homoleptic VOIV complexes with bidentate heterocycles, namely bipyrazole/pyrimidin-2-amine/triazolopyrimidine derivatives, are novel square pyramidal oxovanadium(IV) complexes. Their identities have been established using physicochemical techniques, namely elemental and spectral (ESI-MS, IR, UV–visible) analyses. The in vitro antibacterial activities against Gram-negative and Gram-positive microorganisms have been studied for all compounds, exhibiting good inhibition as compared to the ligands. In addition, all compounds exhibit significant cytotoxicity towards brine shrimp with LD50 values obtained in the range 8–24 μg ml−1. Cellular level cytotoxicity has been investigated using bioassay of Schizosaccharomyces pombe, the complexes showing inevitable viability as concentration increases. Notably, UV absorption spectral titrations of the synthesized complexes with DNA reveal that the complexes bind to calf thymus DNA (CT-DNA) through intercalation mode (Kb = 104–105 M−1). Molecular docking reveals that the compounds are stacked between the base pairs of DNA. The results suggest that the complexes show promising binding affinity compared to the ligands towards CT-DNA.Influence on biological response of substituted pyrazole-incorporated heterocyclic scaffolds and their oxovanadium complexes.
      PubDate: 2017-03-30T04:31:23.127122-05:
      DOI: 10.1002/aoc.3767
       
  • Synthesis, characterization, cytotoxicity and computational studies of new
           phosphine- and carbodithioate-based palladium(II) complexes
    • Authors: Hamid Nawaz; Amir Waseem, Zia-ur-Rehman, Muhammad Nafees, Muhammad Nadeem Arshad, Umer Rashid
      Abstract: In quest of new metallo-pharmaceuticals with enhanced anticancer activity, four new phosphine- and carbodithioate-based Pd(II) complexes of the type [(R)CS2Pd(PR3)Cl] (where R = 4-(2-hydroxyethyl)piperazine (1, 2), dibenzyl (3, 4); PR3 = diphenyl(p-tolyl)phosphine (1, 3), tris(4-tolyl)phosphine (2, 4)) were synthesized and characterized using elemental analysis, Fourier transform infrared and NMR (1H, 13C and 31P) spectroscopies and single-crystal X-ray diffraction. The X-ray diffraction data confirmed the pseudo square-planar geometry ensuring bidentate coordination mode of carbodithioate ligands. Anticancer activity of the synthesized complexes and their ligands was assessed against human lung (A549), breast (MCF-7) and prostate (PC3) carcinoma cells using MTT assay. All the tested compounds showed activity in micromolar range. In many cases, the cytotoxicity of the synthesized complexes was higher than or comparable to that of the standard drugs cisplatin and doxorubicin. Complex 3 emerged as the most promising compound with the lowest IC50 values of 4.83, 3.72 and 5.11 μM for A549, MCF-7 and PC3 carcinoma cell lines, respectively. DNA binding studies were also carried out using UV–visible spectroscopy. We extended our investigations to explore the mechanism of anticancer activity using in silico tools. Based on the mechanism of action of standard drugs used, extensive docking studies were carried out on the three different biomolecular targets.Four new phosphine- and carbodithioate-based Pd(II) complexes were synthesized and characterized. Frontier molecular orbital (HOMO–LUMO) energies were calculated using Gaussian 09. In MTT assay, complex 3 showed the highest activity on all tested cell lines. In vitro activity was complemented by docking studies.
      PubDate: 2017-03-30T04:31:04.213171-05:
      DOI: 10.1002/aoc.3771
       
  • Electrochemical and photocatalytic hydrogen evolution by an
           electron-deficient cobalt tris(ethoxycarbonyl)corrole complex
    • Authors: Hui-Qing Yuan; Hua-Hua Wang, Jaipal Kandhadi, Hui Wang, Shu-Zhong Zhan, Hai-Yang Liu
      Abstract: An electron-deficient flat 5,10,15-tris(ethoxycarbonyl)corrole (TECC) cobalt complex, [Co(TECC)(Py)2] (1; py = pyridine), was prepared and employed as a catalyst for homogeneous hydrogen evolution. It turns out that water can be successfully used as a proton source in acetonitrile–water (2:3 v/v) solvent system for electrocatalytic hydrogen evolution. Complex 1 is also an efficient photocatalyst for hydrogen generation from aqueous solution, an example of the first application of metal corrole as photocatalyst for hydrogen production.Cobalt tris(ethoxycarbonyl)corrole complex can be employed as catalyst for electrochemical and photochemical proton reduction from aqueous media.
      PubDate: 2017-03-30T04:26:31.844291-05:
      DOI: 10.1002/aoc.3773
       
  • Two two-dimensional supramolecular copper(II) and cobalt(III) complexes
           derived from a new quinazoline-type ligand: Syntheses, structures, and
           spectral, thermal, electrochemical and antimicrobial activity studies
    • Authors: Lan-Qin Chai; Li-Jian Tang, Kong-Yan Zhang, Jian-Yu Zhang, Hong-Song Zhang
      Abstract: Two two-dimensional supramolecular copper(II) and cobalt(III) complexes, Cu(L1)2 (1; HL1 = 2-hydroxy-3-methoxybenzaldehyde oxime) and [Co(L2)2]2⋅2CH3COOCH2CH3 (2; HL2 = 1-(2-{[(E)-3-methoxy-2-hydroxybenzylidene]amino}phenyl)ethanone oxime), have been synthesized via complexation of Cu(II) nitrate trihydrate and Co(II) acetate tetrahydrate with HL. A plausible reaction mechanism for the formation of HL1 is proposed. HL was synthesized and characterized using infrared, 1H NMR and 13C NMR spectra, as well as elemental analysis. Complexes 1 and 2 were investigated using single-crystal X-ray diffraction and have a 2:1 ligand-to-metal ratio. Different geometric features of both complexes are observed. In their crystal structures, 1 and 2 form infinite two-dimensional structures and 2 forms a three-dimensional supramolecular framework. Electron paramagnetic resonance spectra of 1 and 2 were also investigated. Moreover, thermal and electrochemical properties and antimicrobial activity of 2 were also studied. In addition, the calculated HOMO and LUMO energies show the character of complex 1.Two-dimensional supramolecular copper(II) and cobalt(III) complexes were synthesized from a quinazoline-type ligand. EPR spectra of the complexes were investigated. Thermal and electrochemical properties and antimicrobial activity of the Co(III) complex were also studied. The calculated HOMO and LUMO energies show the character of the Cu(II) complex.
      PubDate: 2017-03-30T04:26:23.877549-05:
      DOI: 10.1002/aoc.3786
       
  • Green synthesis of reduced graphene oxide/Fe3O4/Ag ternary nanohybrid and
           its application as magnetically recoverable catalyst in the reduction of
           4-nitrophenol
    • Authors: Tran Viet Thu; Pil Ju Ko, To Van Nguyen, Nguyen Thanh Vinh, Doan Minh Khai, Le Trong Lu
      Abstract: Materials having both magnetic and catalytic properties have shown great potential for practical applications. Here, a reduced graphene oxide/iron oxide/silver nanohybrid (rGO/Fe3O4/Ag NH) ternary material was prepared by green synthesis of Ag on pre-synthesized rGO/Fe3O4. The as-prepared rGO/Fe3O4/Ag NH was characterized using Fourier transform infrared spectroscopy, X-ray diffractometry, Raman spectroscopy, vibrating sample magnetometry, transmission electron microscopy and energy-dispersive X-ray spectroscopy. rGO sheets were covered with Fe3O4 (8–16 nm) and Ag (18–40 nm) nanoparticles at high densities. The mass percentages were 13.47% (rGO), 62.52% (Fe3O4) and 24.01% (Ag). rGO/Fe3O4/Ag NH exhibited superparamagnetic behavior with high saturated magnetization (29 emu g−1 at 12 kOe), and efficiently catalyzed the reduction of 4-nitrophenol (4-NP) with a rate constant of 0.37 min−1, comparable to those of Ag-based nanocatalysts. The half-life of 4-NP in the presence of rGO/Fe3O4/Ag NH was ca 1.86 min. rGO/Fe3O4/Ag NH could be magnetically collected and reused, and retained a high conversion efficiency of 94.4% after the fourth cycle. rGO/Fe3O4/Ag NH could potentially be used as a magnetically recoverable catalyst in the reduction of 4-NP and environmental remediation.A superparamagnetic reduced graphene oxide/iron oxide/silver nanohybrid was synthesized using a green method. The nanohybrid efficiently catalyzed the reduction of 4-nitrophenol and could be magnetically recovered and reused multiple times.
      PubDate: 2017-03-30T04:25:45.357513-05:
      DOI: 10.1002/aoc.3781
       
  • Synthesis of poly(propylene imine) dendrimers via homogeneous reduction
           process using lithium aluminium hydride: Bioconjugation with folic acid
           and doxorubicin release kinetics
    • Authors: Marzieh Golshan; Mehdi Salami-Kalajahi, Hossein Roghani-Mamaqani, Maryam Mohammadi
      Abstract: The heterogeneous reduction process for synthesis of poly(propylene imine) (PPI) dendrimer has been replaced by a novel and homogeneous process. Accordingly, to prepare half generations, acrylonitrile was added to amine groups via Michael addition reaction. Then, nitrile groups were reduced via homogeneous hydrogenation using lithium aluminium hydride to synthesize fifth-generation PPI dendrimers with ethylenediamine core. Also, peripheral primary amine groups were conjugated with folic acid (FA). Fourier transform infrared and 13C NMR spectroscopies and gel permeation chromatograph y were used to prove the synthesis of the various structures. Finally fifth-generation and FA-conjugated fifth-generation PPI dendrimers were loaded with doxorubicin and exposed to environments with different pH values to examine the release properties of the structures. Also, drug release kinetics was investigated by fitting experimental data with various release models. The synthesized dendritic structures showed Higuchi model release behaviour due to better solubility of drug in release media with respect to dendrimer cavities.A simple Homogeneous process is used to synthesize PPI dendrimers utilizing Michael addition and subsequent lithium aluminum hydride as homogeneous reduction (hydrogenation) catalyst.
      PubDate: 2017-03-30T04:20:28.921008-05:
      DOI: 10.1002/aoc.3789
       
  • Coumarin-tethered (benz)imidazolium salts and their silver(I)
           N-heterocyclic carbene complexes: Synthesis, characterization, crystal
           structure and antibacterial studies
    • Authors: Gautam Achar, Ramya V. C; Upendranath K, Srinivasa Budagumpi
      Abstract: A series of new sterically modulated chlorocoumarin-substituted (benz)imidazolium salts and their bis-N-heterocyclic carbene silver(I) complexes were prepared and characterized. The complexes were prepared in good yields following the in situ deprotonation method by treating azolium salts with silver(I) oxide in the dark. All the compounds were characterized using various spectroscopic and analytical methods. Additionally, one of the benzimidazolium salts was characterized using single-crystal X-ray diffraction technique. In this salt, intermolecular π–π stacking interactions operate between benzimidazole as well as coumarin heterocyclic systems with adjacent molecules. In the preliminary antibacterial studies, the silver complexes were found more active than the corresponding salts against a panel of bacterial strains. Interestingly, the complexes displayed improved antibacterial efficacy against Escherichia coli strain, comparable with that of the standard drug ampicillin.A series of Ag-NHC complexes are prepared and characterized by spectral and analytical methods. Structure of a benzimidazole salt, 4, was studied by single crystal XRD method. Antibacterial activity of salts and complexes was studied.
      PubDate: 2017-03-30T04:10:53.552102-05:
      DOI: 10.1002/aoc.3770
       
  • Chemosensing hybrid materials: Chalcones-functionalized cage-like
           mesoporous SBA-16 material for highly selective detection of toxic metal
           ions
    • Authors: Marwa N. El-Nahass; Tarek A. Fayed
      Abstract: Highly selective and low-cost optical nanosensors of organic–inorganic hybrid materials for heavy metal ions detection have been prepared via the functionalization of mesoporous silica (SBA-16) with chalcone fluorescent chromophores. The successful attachment of organic chalcone moieties and preservation of original structure of SBA-16 after the anchoring process were confirmed by extensive characterizations using various techniques like Fourier transform infrared and UV–visible spectroscopies, transmission electron microscopy, nitrogen adsorption–desorption isotherms, low-angle X-ray diffraction and thermogravimetric analysis. The colorimetric behaviour, selectivity and sensitivity were also investigated. The optical nanosensors respond selectively to heavy metal ions, such as Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+ and Hg2+, with observable colour changes in 0.01 M Tris–HCl aqueous buffer solution. Also, the optical sensing ability of the investigated nanosensors to the mentioned metal ions was investigated using steady-state absorption and emission techniques. Significant increase in the absorption spectra and a static quenching in the emission spectra are observed upon adding various concentrations of the studied metal ions. The spectral changes as well as the observable colour changes suggest that the investigated nanosensors are suitable for simple, economic, online analysis and remote design of these toxic metal ions with fast kinetic responses. Finally, the low detection limits for all the studied metals are in good agreement with those recommended by both the US Environmental Protection Agency and World Health Organization, except for Hg2+ and Cd2+, indicating that the investigated nanosensors have hypersensitivity, selectivity and better recognition for all the studied metal ions.Highly selective and low cost optical nanosensors of organic-inorganic hybrid materials for heavy metal ion detection have been synthesized.The optical nanosensors respond selectively and sensitivity to the mentioned metal ions.The low detection limits for the studied metals are in good agreement with those recommended by both the US Environmental Protection Agency and World Health Organization, except for Hg2+ and Cd2+, indicating that the investigated nanosensors have hypersensitivity, selectivity and better recognition for all the studied metal ions.
      PubDate: 2017-03-30T04:05:43.984599-05:
      DOI: 10.1002/aoc.3751
       
  • Gold nanoparticles supported on ionic liquid-modified cellulose as an
           efficient and recyclable catalyst for the oxidation of alcohols to
           aldehydes/ketones and reduction of nitroarenes
    • Authors: Ali Pourjavadi; Zahra Habibi
      Abstract: A novel catalyst of gold nanoparticles supported on cellulose fibres with the ionic liquid framework (Au NPs@CL-IL) has been shown to be a highly active and recyclable catalyst for the oxidation of primary and secondary alcohols and reduction of nitroarenes in aqueous media. The reusability of this catalyst is high, and it can be reused ten times without a significant decrease in its catalytic activity. Furthermore, transmission electron micrographs of the recovered catalyst show the presence of well-distributed Au NPs on the CL-IL fibres without any aggregation.A novel catalyst of gold nanoparticles supported on cellulose fibres with ionic liquid framework (Au NPs@CL-IL) has been shown to be a highly active and recyclable catalyst for the oxidation of primary and secondary alcohols and reduction of nitroarenes in aqueous media.
      PubDate: 2017-03-30T04:03:37.398159-05:
      DOI: 10.1002/aoc.3783
       
  • Manganese(II) tetrasulfophthalocyanine covalently supported on natural
           silk: A new highly active catalyst for synthesis of benzoxazepine
           derivatives in water
    • Authors: Zeinab Hezarkhani; Mohammad Tayeb Faroghi, Ahmad Shaabani
      Abstract: Natural silk as a biodegradable, biocompatible, renewable, green and abundant biomaterial was used as a support for chemical immobilization of a water-soluble manganese(II) complex with a phthalocyanine ligand possessing covalent binding ability. The prepared manganese(II) tetrasulfophthalocyanine complex supported on natural silk revealed efficient catalytic activity and reusability for the synthesis of benzoxazepine derivatives in water at room temperature.Chemical immobilization of a water-soluble manganese(II) complex with a phthalocyanine ligand possessing covalent binding ability on natural silk was carried out for the preparation of a green catalyst. The catalyst showed efficient catalytic activity and reusability for the synthesis of benzoxazepine derivatives in water at room temperature.
      PubDate: 2017-03-30T03:55:50.684873-05:
      DOI: 10.1002/aoc.3764
       
  • Green synthesis of palladium nanoparticles using Hibiscus sabdariffa L.
           flower extract: Heterogeneous and reusable nanocatalyst in Suzuki coupling
           reactions
    • Authors: Malak Hekmati; Fahimeh Bonyasi, Hadis Javaheri, Saba Hemmati
      Abstract: An elementary and ecological method has been designed for the biosynthesis of palladium nanoparticles, through the utilization of aqueous extract of red tea (Hibiscus sabdariffa L.) as a reducing and stabilizing agent. The nanoparticles obtained were characterized through UV–visible spectroscopy, transmission election microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, scanning election microscopy, energy-dispersive X-ray analysis and inductively coupled plasma analysis. The nanoparticles with spherical shape and dimensions of approximately 10 nm were used as a heterogeneous catalyst for Suzuki coupling reactions under mild conditions. The high efficiency of the catalytic reaction was affirmed by the good yields of products, easy work-up, absence of palladium leached from the support and smooth recovery of catalyst.A successful ecological method for the synthesis of palladium nanoparticles (Pd NPs) using Hibiscus sabdariffa L. flower extract is reported, the NPs being efficient nanocatalyst in the Suzuki coupling reaction.
      PubDate: 2017-03-27T04:37:37.593501-05:
      DOI: 10.1002/aoc.3757
       
  • Plasmonic Ag/AgCl-modified bismuth subcarbonate with enhanced visible
           light photocatalytic activity
    • Authors: Yanting An; Wenrong Cao, Yuanyuan Zhou, Lifang Chen, Zhiwen Qi
      Abstract: Plasmonic Ag/AgCl-modified bismuth subcarbonate (Bi2O2CO3) composites were prepared by a multistep process with hydrothermal, deposition, and photoreduction in the absence of organic capping agents. The properties of the obtained Ag/AgCl/Bi2O2CO3 samples were characterized using X-ray diffraction, field emission scanning electron microscopy and X-ray photoelectron, UV–visible diffuse reflectance, and photoluminescence spectroscopies. The results reveal that Ag/AgCl nanoparticles are dispersed on the Bi2O2CO3 surface to achieve plasmonic Ag/AgCl/Bi2O2CO3. The Ag/AgCl/Bi2O2CO3 nanocomposites show improved rhodamine B (RhB) adsorption capacity and photocatalytic activity compared with pure Bi2O2CO3 and Ag/AgCl. In addition, the Ag/AgCl/Bi2O2CO3 composite with 20 wt% Ag/AgCl exhibits the highest photocatalytic activity and remains stable for the photodegradation of RhB under visible light. The enhanced photocatalytic activity of Ag/AgCl/Bi2O2CO3 may be attributed to the surface plasmon resonance effect of in situ generated Ag nanoparticles and synergistic effect of Ag/AgCl and Bi2O2CO3, which increase the separation efficiency of photogenerated electron–hole pairs under visible light irradiation.The enhanced photocatalytic activity of plasmonic Ag/AgCl/Bi2O2CO3 may be attributed to the surface plasmon resonance effect of in situ generated Ag nanoparticles and synergistic effect of Ag/AgCl and Bi2O2CO3, which increase the separation efficiency of photogenerated electron–hole pairs under visible light irradiation.
      PubDate: 2017-03-27T01:30:42.663749-05:
      DOI: 10.1002/aoc.3777
       
  • Biocatalysis, DNA–protein interactions, cytotoxicity and molecular
           docking of Cu(II), Ni(II), Zn(II) and V(IV) Schiff base complexes
    • Authors: Chithiraivel Balakrishnan; M. Theetharappan, P. Kowsalya, Satheesh Natarajan, M.A. Neelakantan, S.S. Mariappan
      Abstract: Four mononuclear metal complexes (Cu(II) (1), Ni(II) (2), Zn(II) (3) and V(IV) (4)) were synthesized using the Schiff base ligand 2,2′-{cyclohexane-1,2-diylbis[nitrilo(1E)eth-1-yl-1-ylidine]}bis[5-(prop-2-yn-1-yloxy)phenol] and structurally characterized by various spectral techniques. The catecholase-mimicking activities of 1–4 were investigated and the results reveal that all the complexes have ability to oxidize 3,5-di-tert-butylcatechol (3,5-DTBC) to 3,5-di-tert-butylquinone in aerobic conditions. Electrospray ionization mass spectrometry studies were performed for 1–4 in the presence of 3,5-DTBC to determine the possible complex–substrate intermediates. X-band electron paramagnetic resonance spectroscopy results indicate that the metal centres are involved in the catecholase activity. Ligand-centred radical generation was further confirmed by density functional theory calculation. The phosphatase-like activity of 1–4 was investigated using 4-nitrophenylphosphate as a model substrate. All the complexes exhibit excellent phosphatase activity in acetonitrile medium. The interactions of 1–4 with calf thymus DNA (CT-DNA) and bovine serum albumin (BSA) protein were investigated using absorption and fluorescence titration methods. All the complexes strongly interact with CT-DNA and BSA protein. The complexes exhibit significant hydrolytic cleavage of supercoiled pUC19 DNA. Complexes 1–4 exhibit significant in vitro cytotoxicity against MCF7 (human breast cancer) and MIA-PA-CA-2 (human pancreatic cancer) cell lines. Moreover, the molecular docking technique was employed to determine the binding affinity with DNA and protein molecules.Four mononuclear metal complexes containing a Schiff base ligand (2,2'-{cyclohexane-1,2-diylbis[nitrilo(1E)eth-1-yl-1-ylidine]}bis[5-(prop-2-yn-1-yloxy)phenol])] have been synthesized and characterized. Bio-catalytic and DNA/protein interactions of these metal complexes were evaluated. In vitro cytotoxicity of metal complexes were studied against MCF7 and MIA-PA-CA-2 cell lines.
      PubDate: 2017-03-27T01:26:10.028829-05:
      DOI: 10.1002/aoc.3776
       
  • Synthesis, characterization and biological evaluation of Ru(III)
           mercaptopyrimidine Schiff base complexes
    • Authors: S. Jone Kirubavathy; J. Saranya, N. Sathya, I. V. M. V. Enoch, P. Mosae Selvakumar, S. Chitra
      Abstract: A new series of mercaptopyrimidine Ru(III) complexes were synthesized and characterized using various spectral techniques like single-crystal X-ray diffraction, Fourier transform infrared and NMR spectroscopies, thermogravimetric analysis and energy-dispersive X-ray analysis. The complexes were evaluated for their pharmacological activities like in vitro antimicrobial, anticancer, antituberculosis and antioxidant activities. The DNA binding of the complexes was investigated by absorption and emission spectral measurements which indicated that the complexes bind to DNA via intercalation, with molecular docking studies validating the results. DNA cleavage studies of the complexes were carried out.Four new biologically active Ru(III) mercaptopyrimidine Schiff base complexes were synthesized and characterized. Biological activity includes antimicrobial, anticancer, antituberculosis and antioxidant activities. DNA binding and cleavage studies were conducted along with molecular docking studies. DFT was used to optimize the geometry and calculate HOMO–LUMO gap.
      PubDate: 2017-03-27T01:21:17.979805-05:
      DOI: 10.1002/aoc.3760
       
  • Preparation and characterization of cyclohexandiamine/Fe3O4/ZnO core/shell
           nanomagnetic composite as a novel reusable catalyst and its application
           for the diastereoselective synthesis of β-lactams via the asymmetric
           Kinugasa reaction
    • Authors: Javad Safaei-Ghomi; Safura Zahedi
      Abstract: A novel magnetic composite catalyst has been prepared by immobilizing a chiral diamine on core/shell Fe3O4/ZnO. This new catalyst was characterized using X-ray diffraction, energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis and vibrating sample magnetometry. The performance of the catalyst was investigated in the asymmetric Kinugasa reaction and confirmed to be efficient in the synthesis of β-lactam derivatives under mild conditions.A novel magnetic composite catalyst was prepared by immobilizing a chiral diamine on core/shell Fe3O4/ZnO. This catalyst was characterized using various techniques. The performance of the catalyst was investigated in the asymmetric Kinugasa reaction and confirmed to be efficient in the synthesis of β-lactam derivatives under mild conditions.
      PubDate: 2017-03-27T01:05:33.630527-05:
      DOI: 10.1002/aoc.3763
       
  • Synthesis and catalytic performance of ferrocene-based compounds as
           burning rate catalysts
    • Authors: Zain-ul-Abdin; Li Wang, Haojie Yu, Muhammad Saleem, Muhammad Akram, Hamad Khalid, Nasir M. Abbasi, Rizwan Ullah Khan
      Abstract: To overcome migration problems of ferrocene-based burning rate catalysts and to enhance burning rate of ammonium perchlorate (AP)-based propellants, eleven ferrocene-based compounds (1–11) were synthesized by the condensation reaction of ferrocenecarbonyl chloride with corresponding amines and alcohols. The synthesis of 1–11 was confirmed using 1H NMR, Fourier transform infrared and UV–visible spectroscopy. Their electrochemical properties were analyzed using cyclic voltammetry. The compounds showed redox behavior due to the presence of ferrocene. Their catalytic behavior in the thermal decomposition of AP was investigated using thermogravimetry (TG) and differential TG (DTG). In the presence of 5 wt% 1–11, the thermal decomposition temperature of AP was significantly decreased. TG and DTG analyses showed that 1–11 had a good catalytic effect in the thermal decomposition of AP. Anti-migration studies showed that migration of 1–11 was slower than that of 2,2-bis(ethylferrocenyl)propane (catocene) and ferrocene. The effect of the presence of polar elements like oxygen and nitrogen on anti-migration behavior of small ferrocene-based compounds was also investigated. Oxygen-containing compounds showed better anti-migration behavior than nitrogen-containing compounds.Eleven ferrocene-based compounds were successfully synthesized.Electrochemical and anti-migration properties of the synthesized compounds were analyzed.Burning rate catalytic performance of the synthesized compounds was also investigated on the thermal decomposition of AP.
      PubDate: 2017-03-27T00:55:54.765439-05:
      DOI: 10.1002/aoc.3754
       
  • Sodium cyanide-promoted copper-catalysed aerobic oxidative synthesis of
           esters from aldehydes
    • Authors: Najmeh Nowrouzi; Mohammad Abbasi, Maryam Bagheri
      Abstract: A simple and efficient copper-catalysed procedure for oxidative esterification of aldehydes with alcohols and phenols mediated by sodium cyanide, using air as a clean oxidant, is described. A variety of aromatic aldehydes and structurally different alcohols and phenols reacted efficiently, and the product esters were obtained in good to excellent yields under normal atmospheric and solvent-free conditions.The copper-catalysed oxidative esterification of aldehydes with alcohols and phenols is reported.
      PubDate: 2017-03-27T00:50:32.052312-05:
      DOI: 10.1002/aoc.3766
       
  • Aminophenolates of aluminium, gallium and zinc: Synthesis,
           characterization and polymerization activity
    • Authors: Dariusz Basiak; Łukasz Dobrzycki, Paweł Socha, Patryk Rzepiński, Andrzej Plichta, Krzysztof Bujnowski, Ludwik Synoradzki, Natalia Orłowska, Wanda Ziemkowska
      Abstract: Complexes containing aminophenolate ligands are considered as very efficient initiators of ring-opening polymerization (ROP). Our systematic studies of the reactions of two selected aminophenols, 2-[(p-tolylamino)methyl]-4-(2,4,4-trimethylpentan-2-yl)phenol (L'H2) and 2-cyclohexylaminomethyl-4-methylphenol (L″H2), with alkyl compounds of aluminium, gallium and zinc resulted in the formation of a variety of products depending on the type of metallic centre and alkyl groups bonded to metal atoms. New trinuclear aluminium complexes (Me5Al3(L′)2 (1) and Me5Al3(L″)2 (2)), monomeric aluminium (tBu2Al(L'H) (3) and tBu2Al(L″H) (5)) and gallium (tBu2Ga(L'H) (4) and tBu2Ga(L″H) (6)) compounds, and dinuclear gallium (Et2Ga(L″H)·Et3Ga (7)) and zinc (tBuZn(L″H)]2 (8)) complexes were isolated and characterized. The molecular and crystal structures of 7 and 8 were determined on the basis of an X-ray diffraction study. Polymerization tests showed that only three complexes (6–8) had activity in the ROP of ε-caprolactone, whereas 1–5 were inactive in ROP.Reactions of two selected aminophenols with alkyl compounds of aluminium, gallium and zinc resulted in the formation of a variety of products, which were studied as initiators of ring-opening polymerization.
      PubDate: 2017-03-27T00:36:41.644103-05:
      DOI: 10.1002/aoc.3748
       
  • Mild and eco-friendly chemoselective acylation of amines in aqueous medium
           using a green, superparamagnetic, recoverable nanocatalyst
    • Authors: Maryam Kazemi Miraki; Elahe Yazdani, Leila Ghandi, Kobra Azizi, Akbar Heydari
      Abstract: Copper-grafted guanidine acetic acid-modified magnetite nanoparticles (Fe3O4@GAA-Cu(II)) as a green, superparamagnetic and recoverable nanocatalyst is found to promote quantitative N-acylation of various amines in a very short time with an equimolar amount of thioacetic acid in water at room temperature. This method is found to be highly selective for amines and not sensitive to other functional groups. Mild reaction condition, high selectivity, efficiency, simple workup and excellent yields are some of the major advantages of the procedure.Copper-grafted guanidine acetic acid-modified magnetite nanoparticles (Fe3O4@GAA-Cu(ӀӀ)) as a green, superparamagnetic and recoverable nanocatalyst is found to promote quantitative N-acylation of various amines in a very short time with an equimolar amount of thioacetic acid in water at room temperature.
      PubDate: 2017-03-20T02:36:03.380945-05:
      DOI: 10.1002/aoc.3744
       
  • Novel hybrid transition metal complexes of
           diaquabis(acetylacetonato-κ2o,o′)[nickel(II)/zinc (II)] as solid
           metal–organic precursors: Synthesis, properties and magnetic response
    • Authors: Matin Roshanzamir Modaberi; Sanjaya Brahma, Reza Rooydell, Ruey-Chi Wang, Chuan-Pu Liu
      Abstract: A series of hybrid hetero bimetallic metal–organic frameworks, as solid metal–organic precursors, have been prepared via a conventional hydrothermal method. Herein, we report a facile approach for the synthesis of novel crystalline organic–inorganic hybrid compounds of diaquabis(acetylacetonato)[nickel(II)/zinc(II)] in the presence of varying mole ratios of Ni(II)/Zn(II) mixed metal ions. C10H18O6Ni0.7Zn0.3 (N0.7Z0.3AA.2H2O) as an instance of the series has been investigated through detailed characterization. The crystal is composed of N0.7Z0.3AA units and two coordinated water molecules to form a monoclinic structure with space group P21/c. All the solid-state structures have the metals in octahedral environments forming six-membered chelate rings. The unit cell dimensions were obtained using single-crystal X-ray diffraction. Thermogravimetric analysis reveals that the hybrid compounds can be considered as suitable precursors for the synthesis of oxides via metal–organic chemical vapour deposition. At room temperature, all crystals clearly exhibit paramagnetic behaviour. Besides varying molar ratios of hybrid, the transition point of magnetic behaviour occurs at Ni critical concentration of around 10% in the hybrid. In addition, the magnetic susceptibility increases with increasing Ni content in the compounds.A series of Ni/Zn acetylacetonate hybrids were prepared via a hydrothermal method. The characterization of C10H18O6Ni0.7Zn0.3 as a solid metal–organic compound was investigated. Th hybrids can be considered as suitable precursors for the synthesis of oxides via metal–organic chemical vapour deposition. Transition point of magnetic behaviour at critical Ni concentration was predicted by varying molar ratios of atoms in the hybrids.
      PubDate: 2017-03-10T04:28:28.030758-05:
      DOI: 10.1002/aoc.3746
       
  • Supported palladium nanoparticle-catalysed Suzuki–Miyaura cross-coupling
           approach for synthesis of aminoarylbenzosuberene analogues from natural
           precursor
    • Authors: Richa Bharti; C. Bal Reddy, Sandeep Kumar, Pralay Das
      Abstract: A semi-synthetic method has been developed for the synthesis of aminoarylbenzosuberenes (AABs) from naturally occurring himachalenes, an isomeric mixture of sesquiterpenes present in Cedrus deodara oil. Polymer-stabilized Pd(0) nanoparticle-catalysed Suzuki–Miyaura cross-coupling reaction of aminovinyl bromide-substituted benzosuberenes has been adopted for AAB synthesis. The catalyst performed well with different amine substituents, and was recycled up to five times. The synthesis of such arylated benzosuberene class of compounds from natural precursors following semi-synthetic approaches could provide an attractive alternative method with reduced number of steps.A semi-synthetic method has been developed for the synthesis of aminoarylbenzosuberenes (AABs) from naturally occurring himachalenes, an isomeric mixture of sesquiterpenes present in Cedrus deodara oil. Polymer-stabilized Pd(0) (Pd@PS) nanoparticle-catalysed Suzuki–Miyaura cross-coupling reaction of aminovinyl bromide-substituted benzosuberenes has been adopted for AAB synthesis.
      PubDate: 2017-03-10T04:28:16.63501-05:0
      DOI: 10.1002/aoc.3749
       
  • Modified cyclopentadienyl molybdenum compounds with enhanced cytotoxic
           activity towards MOLT-4 leukaemia cells
    • Authors: Iva Honzíčková; Jaromír Vinklárek, Zdeňka Růžičková, Martina Řezáčová, Jan Honzíček
      Abstract: A series of new cyclopentadienyl molybdenum compounds bearing substituted phenanthroline ligands [(η5-C5H4CH2C6H4X-4)Mo(CO)2(N,NL)][BF4] (X = F, Cl, Br; N,NL = phen, 5-NH2-phen, 4,7-Ph2-phen) was prepared and characterized using infrared and NMR spectroscopies. Crystal structures of [(η5-C5H4CH2C6H4F-4)Mo(CO)2(NCMe)2][BF4], [(η5-C5H4CH2C6H4X-4)Mo(CO)2(phen)][BF4] (X = F, Cl, Br) and [(η5-C5H4CH2C6H4Cl-4)Mo(CO)2(4,7-Ph2-phen)][BF4]⋅(4,7-Ph2-phen)⋅HBF4 were determined using X-ray diffraction analysis. Biological studies revealed a strong cytotoxic effect of the chelating ligands. Although the cytostatic effect of the halogen in the side chain of the cyclopentadienyl ring is negligible, it could be used for future post-modification of these types of cytotoxic active molybdenum-based compounds.A series of new cyclopentadienyl molybdenum compounds bearing substituted phenanthroline was prepared and characterized using spectroscopic methods and X-ray crystallography. Biological studies revealed the strong cytotoxic effect of chelating ligands. The halogen in the side chain of the cyclopentadienyl ring could be used for future post-modification.
      PubDate: 2017-03-10T04:28:11.241292-05:
      DOI: 10.1002/aoc.3759
       
  • Selective and sensitive determination of silver ions at trace levels based
           on ultrasonic-assisted dispersive solid-phase extraction using
           ion-imprinted polymer nanoparticles
    • Authors: Mohammad Behbahani; Fariborz Omidi, Masoud Ghanbari Kakavandi, Ghasem Hesam
      Abstract: We describe ultrasonic-assisted dispersive solid-phase extraction based on ion-imprinted polymer (UA-DSPE-IIP) nanoparticles for the selective extraction of silver ions. Ultrasound is a good and robust method to facilitate the extraction of target ions in the sorption step and elution of the target ions in the desorption step. The IIP nanoparticles used in the UA-DSPE-IIP were prepared by precipitation polymerization. To prepare the IIP nanoparticles, 2-vinylpyridine, ethylene glycol dimethacrylate, 2,2′-azobisisobutyronitrile, 2-picolinic acid, silver and chloroform–methanol (50:50) solution were used as functional monomer, cross-linker, initiator, silver-binding ligand, template ion and porogen, respectively. The IIP nanoparticles were characterized using Fourier transformed infrared spectroscopy, thermogravimetric and differential thermal analysis, X-ray diffraction and scanning electron microscopy. A Box–Behnken design was used for optimization of sorption and desorption steps in UA-DSPE-IIP. In the sorption step: pH of solution, IIP amount (mg), sonication time for sorption (min); in the desorption step: concentration of eluent (mol l−1), volume of eluent (ml), sonication time (min) for desorption were investigated and optimized by Box–Behnken design. The optimum conditions for the method were: pH of solution, 7; sonication time for sorption, 7 min; IIP amount, 17 mg; type and concentration of eluent, HCl 1.5 mol l−1; volume of eluent, 2 ml; sonication time for desorption, 140 s. Under the optimized conditions the limit of detection and relative standard deviation for the detection of silver ions using UA-DSPE-IIP were found to be 0.09 μg l−1 and
      PubDate: 2017-02-24T01:40:29.975997-05:
      DOI: 10.1002/aoc.3758
       
  • Cobalt complexes based on hyperbranched salicylaldimine ligands as
           catalyst precursors for ethylene oligomerization
    • Authors: Cuiqin Li; Fengfeng Wang, Zhiyu Lin, Na Zhang, Jun Wang
      Abstract: Three hyperbranched salicylaldimine ligands with tetradecyl as core, with hexadecyl as core and with octadecyl as core were synthesized in good yields. These ligands were reacted with cobalt chloride hexahydrate to form three complexes (C1–C3). The compounds were characterized using Fourier transform infrared, 1H NMR, mass and UV spectroscopies and thermogravimetric and differential thermal analyses. The catalytic properties of the hyperbranched cobalt complexes were evaluated for ethylene oligomerization. The effects of solvent and reaction parameters (Al/Co molar ratio, temperature and reaction pressure) on ethylene oligomerization were studied using the cobalt complex C3 as pre-catalyst and methylaluminoxane (MAO) as co-catalyst. Under these conditions ([Co] = 5 μmol, Al/Co = 500, 25 °C, 0.5 MPa ethylene, 30 min), the catalytic activity of complex C3 in toluene was 1.85 × 105 g (mol Co)−1 h−1 and the selectivity for C8+ oligomers was 55.72%. The complex structure also had a significant influence on both the catalytic activity and selectivity. All three cobalt complexes, activated with MAO, showed moderate activities towards ethylene oligomerization and the activity of cobalt complex C1 was up to 1.99 × 105 g (mol Co)−1 h−1. The kinds of metal center of complexes (cobalt complex C1 and nickel complex with tetradecyl as core) and their catalytic properties were investigated in detail under the same conditions.A series of novel hyperbranched salicylaldimine ligands and their cobalt complexes were synthesized and characterized. Upon activation with methylaluminoxane, all three cobalt complexes showed good to excellent activity towards ethylene oligomerization with activities up to 1.93 × 105 g (mol Co)−1 h−1 and selectivity for C8+ oligomers up to 55.72%.
      PubDate: 2017-02-24T01:36:41.155495-05:
      DOI: 10.1002/aoc.3756
       
  • Highly dispersed copper/ppm palladium nanoparticles as novel magnetically
           recoverable catalyst for Suzuki reaction under aqueous conditions at room
           temperature
    • Authors: Kamran Lamei; Hossein Eshghi, Mehdi Bakavoli, Sadegh Rostamnia
      Abstract: An efficient procedure based on arginine-modified Fe3O4@carbon magnetic nanoparticles (FCA MNPs) with highly dispersed copper nanoparticles (Cu NPs) and 92.8 ppm of Pd is reported for room temperature Suzuki reaction. For enhancing the activity of this Cu-based heterogeneous catalyst, special arginine amino acid as a ligand with high content of heteroatoms was immobilized onto the Fe3O4@carbon MNPs to increase the electron density. Cu(II) ions were then loaded on the surface of the FCA MNPs and reduced to achieve uniformly dispersed Cu NPs. An aqueous mixture of metal hydroxides such as KOH, Ba(OH)2, Ca(OH)2, Mg(OH)2 as a green, non-toxic and basic medium was used for the Suzuki reaction at room temperature. This catalyst could also be recovered and reused with no loss of activity over six successful runs.An efficient procedure based on arginine-modified Fe3O4@Carbon magnetic nanoparticles (FCA MNPs) with highly dispersed copper nanoparticles and 92.8 ppm of Pd in aqueous mixture of metal hydroxides such as KOH, Ba(OH)2, Ca(OH)2, Mg(OH)2 as a green non-toxic and basic medium were reported for room temperature Suzuki reaction.
      PubDate: 2017-02-22T06:21:16.269001-05:
      DOI: 10.1002/aoc.3743
       
  • Active and recyclable ordered mesoporous magnetic organometallic catalyst
           as high-performance visible light photocatalyst for degradation of organic
           pollutants
    • Authors: Razieh Nejat; Masoumeh Chamack, Alireza Mahjoub
      Abstract: A novel light-active magnetic Pd complex as a photocatalyst was prepared through bonding organometallics to mesoporous silica channels formed on the surface of silica-coated iron oxide nanoparticles. The nanocomposite (denoted as Fe3O4@SiO2@m-SiO2@PDA-Pd(0); PDA = 1,10-phenanthroline-2,9-dicarbaldehyde) is more efficient and has higher photocatalytic capability in the degradation of 2,4-dichlorophenol under visible light irradiation compared with virgin Pd complex (PDA-Pd). This noteworthy photodegradation activity can be due to the high dispersion of Pd nanoparticles. High yield, low reaction time and non-toxicity of the catalyst are the main merits of this protocol. Also magnetic separation is an environmentally friendly alternative method for the separation and recovery of the catalyst, since it minimizes the use of solvents and auxiliary materials, reduces operation time and minimizes catalyst loss by preventing mass loss and oxidation. The produced Pd catalyst was characterised using various techniques. Furthermore, transmission electron microscopy characterization was used for determining the structural properties of the Pd nanocatalyst.A novel magnetic Pd photocatalyst was prepared through bonding organometallics to mesoporous silica channels which are formed on the surface of silica-coated iron oxide nanoparticles. It is an efficient and recyclable photocatalyst in the degradation of 2,4-dichlorophenol under visible light irradiation.
      PubDate: 2017-02-20T01:25:42.607592-05:
      DOI: 10.1002/aoc.3745
       
  • Photocatalytic degradation of methyl orange using hematoporphyrin/N-doped
           TiO2 nanohybrids under visible light: Kinetics and energy consumption
    • Authors: Javad Saien; Zohreh Mesgari
      Abstract: Various nitrogen-doped titania particles were prepared and, for visible light sensitizing, the biological pigment hematoporphyrin was grafted onto their surfaces. The nanohybrid products were characterized using X-ray diffraction, Fourier transform infrared and ultraviolet–visible spectroscopies and Brunauer–Emmett–Teller surface area analysis. A high-performance visible light helical flow photoreactor was designed and used for the photocatalytic degradation of methyl orange (MO) over these photocatalyst products. Accordingly, response surface methodology was employed for design of experiments and optimization. The influencing parameters were initial N/Ti molar ratio, dosage of nanohybrids and solution pH. These parameters were statistically significant and a quadratic correlation was developed for degradation efficiency (DE) variations. A maximum DE of 89.2% was attainable, after 60 min treatment, under the optimum conditions of initial N/Ti molar ratio of 4.93 (ca 5), nanohybrid dosage of 0.73 g l−1 and pH of 4.8. The MO degradation kinetics over the catalyst surface followed the modified Langmuir–Hinshelwood model. The important role of hydroxyl radicals was confirmed using mannitol scavenger. Performing the photocatalytic reaction with the developed set-up showed excellent efficiency and energy consumption in comparison with similar processes.✓ Various nanohybrids of hematoporphyrin/N-doped TiO2 were synthesized and utilized under visible light. ✓ The influence of initial N/Ti molar ratio, dosage of nanohybrids and pH on catalyst activity was evaluated. ✓ Maximum efficiency of 89.2% was achieved for degradation of methyl orange under the determined optimum conditions. ✓ The introduced helical flow photoreactor exhibits high efficiency with low energy consumption.
      PubDate: 2017-02-20T01:15:46.210404-05:
      DOI: 10.1002/aoc.3755
       
  • Three novel Ni(II), VO(II) and Cr(III) mononuclear complexes encompassing
           potentially tridentate imine ligand: Synthesis, structural
           characterization, DNA interaction, antimicrobial evaluation and anticancer
           activity
    • Authors: Laila H. Abdel-Rahman; Ahmed M. Abu-Dief, Maram Basha, Azza A. Hassan Abdel-Mawgoud
      Abstract: Three novel Cr(III),VO(II) and Ni(II) imine complexes derived from the condensation of 2-aminophenol (AP) with 2-hydroxynaphthaldehyde (HN) were synthesized. The prepared HNAP imine ligand and its complexes were investigated via various physicochemical tools. The results suggest that the parent ligand behaves as a dibasic tridentate ONO ligand, when coordinated to Cr(III) in octahedral and to Ni(II) in tetrahedral geometry. In the case of VO(II), it coordinates in distorted square pyramidal geometry. Also, the prepared compounds were screened for their antimicrobial activities against pathogenic bacteria, Escherichia coli (−ve), Bacillus subtilis (+ve) and Staphylococcus aureus (+ve), and some types of fungi, Aspergillus niger, Candida glabrata and Trichophyton rubrum. The results indicate that the complexes show a stronger antimicrobial efficiency compared to the pro-ligand. The interaction of the prepared complexes with calf thymus DNA was investigated using spectral, viscosity and gel electrophoresis measurements. The obtained results clearly demonstrate that the binding affinity with calf thymus DNA follows the order HNAPCr> HNAPV> HNAPNi. The cytotoxic activity of the prepared compounds on human colon carcinoma cells (HCT-116 cell line), hepatic cellular carcinoma cells (HepG-2cell line) and breast carcinoma cells (MCF-7cell line) was examined. From these results it is found that the investigated complexes have potent cytotoxicity against growth of carcinoma cells compared to the corresponding imine pro-ligand.Three novel Ni(II), VO(II) and Cr (III) imine complexes incorporating tridentate imine ligand have been synthesized and characterized. The prepared complexes have been investigated for their antibacterial and antifungal activity and DNA interaction. The investigated compounds have been tested for their anticancer activity on human colon carcinoma cells, (HCT-116), hepatic cellular carcinoma cells (HepG-2) and breast carcinoma cells (MCF-7).
      PubDate: 2017-02-16T21:10:42.293742-05:
      DOI: 10.1002/aoc.3750
       
  • Two silver(I) complexes with bis(benzimidazole)-2-oxopropane ligands:
           Syntheses, crystal structures and DNA binding studies
    • Authors: Shanshan Mao; Kesheng Shen, Xinkui Shi, Yuling Xu, Huilu Wu
      Abstract: Two Ag(I) complexes, [Ag2(bobb)2]⋅(NO3)2 (1) and [Ag2(crotonate)2(aobb)]n (2) (bobb =1,3-bis(1-benzylbenzimidazol-2-yl)-2-oxapropane; aobb =1,3-bis(1-allylbenzimidazol-2-yl)-2-oxopropane), have been synthesized and characterized using elemental analysis, electrical conductivities, infrared and UV–visible spectral measurements and single-crystal X-ray diffraction. Complex 1 is binuclear and three-coordinated by two N atoms from two bobb ligands, while complex 2 is a unique metal organic compound with diamond-like multinuclear Ag centers with each Ag bridged by two aobb ligands and two crotonate ions to form one-dimensional single polymer chain structures and extended into two-dimensional frameworks through π–π and intermolecular C─H⋅⋅⋅O hydrogen bonds. The adjacent Ag(I) centers are bridged by allyl from aobb which is not only a σ-bonding ligand, but also a π-acid ligand. The DNA binding modes of complexes 1 and 2 were investigated using electronic absorption titration, fluorescence spectra and viscosity measurements. The results suggest that the two complexes bind to DNA via an intercalative mode, and their binding affinity for DNA follows the order 2 > 1. This is due to the chelating effects which can enhance the planar functionality of the metal complexes.Two Ag(I) complexes (1 and 2) with novel structures have been synthesized and characterized systematically. The two complexes bind to DNA in an intercalative mode and DNA binding affinities follow the order: 2 > 1.
      PubDate: 2017-02-16T21:00:41.474654-05:
      DOI: 10.1002/aoc.3747
       
  • (n-Bu2Sn)2O(CO3): An active, robust and recyclable organotin(IV) for the
           direct synthesis of linear organic carbonates from carbon dioxide and
           alcohols
    • Authors: Sreevardhan Reddy Sanapureddy; Laurent Plasseraud
      Pages: 2335 - 2342
      Abstract: Organotin(IV) compounds are known to promote the direct synthesis of organic carbonates from carbon dioxide and alcohols. In the past, structural studies have highlighted that the carbonato moiety is a recurring ligand of tin species collected during CO2 pressurized reactions. In a mimetic approach and in order to achieve an available and recyclable precursor, the title compound (n-Bu2Sn)2O(CO3) (1) was prepared in a single step by reacting commercial di-n-butyltin dichloride with an aqueous solution of sodium carbonate. Compound 1 was characterized using infrared spectroscopy and thermogravimetric and elemental analyses. Multinuclear NMR investigations in solution were also conducted. Compound 1 was then evaluated for the direct carbonation of alcohols (methanol, ethanol, n-butanol and isopropanol) under CO2 pressure. Recycling experiments were performed showing the efficient reuse of 1 without loss of activity. Furthermore, the infrared fingerprint of 1 was preserved even after several runs demonstrating a good stability. The effects of pressure and of reaction time on dimethyl carbonate formation were also studied.(n-Bu2Sn)2O(CO3), prepared in a single step from di-n-butyltin dichloride, was evaluated as a promotor for the direct carbonation of alcohols (methanol, ethanol, n-butanol and isopropanol).
      PubDate: 2017-05-05T00:37:05.660367-05:
      DOI: 10.1002/aoc.3807
       
  • Geometric stability of PtFe/PdFe embedded in graphene and catalytic
           activity for CO oxidation
    • Authors: Wang Rui; Feng Wei, Zhang Dandan, Liu Huiling, Zhao Huanyu, Huang Xuri
      Pages: 2343 - 2350
      Abstract: The direct methanol fuel cell (DMFC) is considered as a promising power source, because of its abundant fuel source, high energy density and environmental friendliness. Among DMFC anode materials, Pt and Pt group metals are considered to be the best electrocatalysts. The combination of Pt with some specific transition metal can reduce the cost and improve the tolerance toward CO poisoning of pure Pt catalysts. In this paper, the geometric stabilities of PtFe/PdFe atoms anchored in graphene sheet and catalytic CO oxidation properties were investigated using the density functional theory method. The results show that the Pt (Pd) and Fe atoms can replace C atoms in graphene sheet. The CO oxidation reaction by molecular O2 on PtFe–graphene and PdFe–graphene was studied. The results show that the Eley–Rideal (ER) mechanism is expected over the Langmuir–Hinshelwood mechanism for CO oxidation on both PtFe–graphene and PdFe–graphene. Further, complete CO oxidation on PtFe–graphene and PdFe–graphene proceeds via a two-step ER reaction: CO(gas) + O2(ads) CO2(ads) + O(ads) and CO(gas) + O(ads) CO2(ads). Our results reveal that PtFe/PdFe commonly embedded in graphene can be used as a catalyst for CO oxidation. The microscopic mechanism of the CO oxidation reaction on the atomic catalysts was explored.Graphene is a good substrate for formulating bimetallic PtFe and PdFe atom catalysts. The most preferable mechanism for studying the CO oxidation reaction over PtFe–graphene and PdFe–graphene is the Eley–Rideal mechanism.
      PubDate: 2017-04-21T02:06:09.930839-05:
      DOI: 10.1002/aoc.3808
       
  • Heteroscorpionate-based heteroleptic copper(II) complexes: Antioxidant,
           molecular docking and in vitro cytotoxicity studies
    • Authors: S. Jayakumar; D. Mahendiran, V. Viswanathan, D. Velmurugan, A. Kalilur Rahiman
      Pages: 2351 - 2364
      Abstract: Three new heteroscorpionate ligands, (2-hydroxyphenyl)bis(imidazol-1-yl)methane (HL1), (4-diethylamino-2-hydroxyphenyl)bis(imidazol-1-yl)methane (HL2) and (5-bromo-2-hydroxyphenyl)bis(imidazol-1-yl)methane (HL3), and their heteroleptic copper(II) complexes of the type [Cu(L1–3)diimine]ClO4 (1–6; where diimine =2,2′-bipyridyl or 1,10-phenanthroline) have been synthesized and characterized using spectroscopic methods. The molecular structure of ligand HL1 was determined by single-crystal X-ray diffraction. UV–visible, electron paramagnetic resonance and theoretical studies suggest a distorted square pyramidal geometry around copper(II) ion. Analyses of highest occupied and lowest unoccupied molecular orbitals have been used to explain the charge transfer taking place within the complexes. The antioxidant activities of the heteroscorpionate ligands and their heteroleptic copper(II) complexes were determined using ABTS, DPPH and H2O2 free radical scavenging assays with respect to standard antioxidant ascorbic acid. In molecular docking studies, the complexes showed π–π, hydrogen bonding, van der Waals and electrostatic interactions with fibroblast growth factor receptor kinase. In vitro cytotoxicity activities of ligands and copper(II) complexes were examined on human breast adenocarcinoma (MCF-7), cervical (HeLa) and lung (A549) cancer cell lines and normal human dermal fibroblast cell line using MTT assay. Complex 4 exhibited higher anticancer activity than the other complexes against all three cancer lines, being more potent than the standard drug cisplatin.Six heteroscorpionate-based heteroleptic copper(II) complexes have been synthesized and characterized. The antioxidant activity was performed using three different methods. In vitro cytotoxicity was performed against three cancerous and one normal cell lines by MTT assay. Molecular docking study was performed with FGFR kinase. The complex containing electron-releasing substituent (─N(C2H5)2) and extended aromaticity exhibit highest biological activity.
      PubDate: 2017-05-22T23:15:39.323831-05:
      DOI: 10.1002/aoc.3809
       
  • Iron-catalyzed carbon–sulfur bond formation: Atom-economic construction
           of thioethers with diaryliodonium salts
    • Authors: Li Liu; Jian Qiang, Shuhua Bai, Yang Li, Jian Li
      Pages: 2365 - 2371
      Abstract: Diaryliodonium salts are characterized by poor atom economy with the formation of one equivalent of an iodoarene as waste. We have developed an atom-economic iron-catalyzed protocol for the synthesis of a variety of thioethers with diaryliodonium salts. Not only cyclic diaryliodonium salts but also linear diaryliodonium salts were found to perform well in the reactions.An atom economic iron-catalyzed protocol for the synthesis of a variety of thioethers with diaryliodonium salts was developed. Not only cyclic diaryliodonium salts but also linear diaryliodonium salts were found to perform well in the reactions.
      PubDate: 2017-04-26T02:16:33.28582-05:0
      DOI: 10.1002/aoc.3810
       
  • Preparation of choline chloride–urea deep eutectic solvent-modified
           magnetic nanoparticles for synthesis of various 2-amino-4H-pyran
           derivatives in water solution
    • Authors: Hossein Tavakol; Fariba Keshavarzipour
      Pages: 2372 - 2380
      Abstract: A novel hybrid magnetic nanocatalyst was synthesized by covalent coating of Fe3O4 magnetic nanoparticles with choline chloride–urea deep eutectic solvent using 3-iodopropyltrimethoxysilane as a linker. The structure of this new catalyst was fully characterized via elemental analysis, transmission and scanning electron microscopies, X-ray diffraction and Fourier transform infrared spectroscopy. It was employed in the synthesis of various 2-amino-4H-pyran derivatives in water solution via an easy and green procedure. The desired products were obtained in high yields via a three-component reaction between aromatic aldehyde, enolizable carbonyl and malononitrile at room temperature. The employed nanocatalyst was easily recovered using a magnetic field and reused four times (in subsequent runs) with less than 8% decrease in its catalytic activity.A novel hybrid nanocatalyst was prepared by covalent coating of magnetite nanoparticles with choline chloride–urea deep eutectic solvent. It was employed in the synthesis of various 2-amino-4H-pyran derivatives in water solution via an easy and green procedure.
      PubDate: 2017-04-27T12:24:38.509248-05:
      DOI: 10.1002/aoc.3811
       
  • A new procedure for determination of nickel in some fake jewelry and
           cosmetics samples after dispersive liquid–liquid microextraction by FAAS
           
    • Authors: Şerife Saçmacı; Mustafa Saçmacı
      Pages: 2381 - 2388
      Abstract: A new, simple and cheap dispersive liquid–liquid microextraction (DLLME) procedure was optimized for the preconcentration of trace amounts of Ni(II) as a prior step to its determination by flame atomic absorption spectrometry (FAAS). It is based on the microextraction of nickel, where appropriate amounts of the extraction solvent (CHCl3), disperser solvent (ethanol) and chelating agent, name 5-[(Z)-isoxazol-3-yl-diazenyl]-2-methyl-quinolin-8-ol (MMD), were firstly synthesized/characterized and used. Various parameters that affect the extraction procedure such as pH, centrifugation rate and time, the chelating agent (MMD) concentration and sampling volume on the recovery of Ni(II) were investigated. The preconcentration of a 20 ml sample solution was thus enhanced by a factor of 80. The resulting calibration graph was linear in the range of 0.24–10 mg L−1 with a correlation coefficient of 0.9998. The limit of detection (3 s/b) obtained under optimal conditions was 1.00 μg L−1. The relative standard deviation for certified reference material determinations was 1.2%. The accuracy of the method was verified by the determination of Ni(II) in the certified reference material of wastewater (Waste water CWW TMD). The proposed procedure was successfully applied to the determination of Ni(II) in some fake jewelry and cosmetics samples.A new microextraction method for determination of Ni.
      PubDate: 2017-09-20T06:21:32.562462-05:
      DOI: 10.1002/aoc.4081
       
  • Self-assembled Pd nanoparticle-containing ionic liquid: Efficient and
           reusable catalyst for the Heck reaction in water
    • Authors: Yingxiao Zong; Junke Wang, Pengli An, Guoren Yue, Yi Pan, Xicun Wang
      Pages: 2389 - 2396
      Abstract: A self-assembled Pd nanoparticle-containing ionic liquid as metal–organic polymer was successfully prepared. The structure of the catalyst was characterized using Fourier transform infrared and 1H NMR spectroscopies, scanning electron microscopy and elemental analysis. The catalyst was effectively employed in the palladium-catalyzed Heck reaction in water as a green solvent. Moreover, due to its stability the catalyst can be recovered simply and effectively and reused nine times without much loss of activity.A self-assembled Pd nanoparticle-containing ionic liquid as metal–organic polymer was successfully prepared. The structure of the catalyst was characterized. The catalyst was effectively employed in the palladium-catalyzed Heck reaction in water as a green solvent. Moreover, due to its stability the catalyst can be recovered simply and effectively and reused nine times without much activity loss.
      PubDate: 2017-03-30T04:20:53.841316-05:
      DOI: 10.1002/aoc.3762
       
  • Chiral Jacobsen's catalyst immobilized on zinc
           poly(styrene-phenylvinylphosphonate)-phosphate functionalized by diamine
           as highly efficient and reusable catalyst for alkene epoxidation
    • Authors: Jing Huang; Yan Luo, Jiali Cai
      Pages: 2397 - 2404
      Abstract: Chiral Jacobsen's catalyst anchored on zinc poly(styrene-phenylvinylphosphonate)-phosphate (ZnPS-PVPA) functionalized by diamines shows superior catalytic activities (conversion up to 99%; enantiomeric excess up to 99%) in the enantioselective epoxidations of unfunctional olefins with m-chloroperoxybenzoic acid and NaIO4 as oxidants. The whole chiral salen Mn(III) catalyst, including the ZnPS-PVPA support and the linker as well as chiral salen Mn ligand together contribute to the chirality of products. The heterogeneous catalyst has the potential for use in industry owing to superior stability (recycling nine times) and activity in large-scale reactions (such as 200 times).Catalysts could be employed in large-scale reactions with superior catalytic disposition.
      PubDate: 2017-04-12T04:36:58.025084-05:
      DOI: 10.1002/aoc.3765
       
 
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
 
Home (Search)
Subjects A-Z
Publishers A-Z
Customise
APIs
Your IP address: 54.224.187.45
 
About JournalTOCs
API
Help
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-2016