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  Subjects -> CHEMISTRY (Total: 841 journals)
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CHEMISTRY (593 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: 23)
ACS Medicinal Chemistry Letters     Full-text available via subscription   (Followers: 39)
ACS Nano     Full-text available via subscription   (Followers: 233)
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: 7)
Adsorption Science & Technology     Full-text available via subscription   (Followers: 5)
Advanced Functional Materials     Hybrid Journal   (Followers: 50)
Advanced Science Focus     Free   (Followers: 3)
Advances in Chemical Engineering and Science     Open Access   (Followers: 55)
Advances in Chemical Science     Open Access   (Followers: 13)
Advances in Chemistry     Open Access   (Followers: 14)
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 Fuel Cells     Full-text available via subscription   (Followers: 15)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 8)
Advances in Materials Physics and Chemistry     Open Access   (Followers: 19)
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: 18)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 19)
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: 68)
American Journal of Biochemistry and Molecular Biology     Open Access   (Followers: 14)
American Journal of Chemistry     Open Access   (Followers: 26)
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: 222)
Angewandte Chemie International Edition     Hybrid Journal   (Followers: 213)
Annales UMCS, Chemia     Open Access   (Followers: 1)
Annals of Clinical Chemistry and Laboratory Medicine     Open Access   (Followers: 3)
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: 295)
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: 4)
Bioorganic & Medicinal Chemistry     Hybrid Journal   (Followers: 121)
Bioorganic & Medicinal Chemistry Letters     Hybrid Journal   (Followers: 98)
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: 3)
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: 6)
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: 13)
Chemical Bulletin of Kazakh National University     Open Access  
Chemical Communications     Full-text available via subscription   (Followers: 70)
Chemical Engineering Research and Design     Hybrid Journal   (Followers: 23)
Chemical Research in Chinese Universities     Hybrid Journal   (Followers: 3)
Chemical Research in Toxicology     Full-text available via subscription   (Followers: 19)
Chemical Reviews     Full-text available via subscription   (Followers: 176)
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: 57)
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: 142)
Chemistry - An Asian Journal     Hybrid Journal   (Followers: 15)
Chemistry and Materials Research     Open Access   (Followers: 18)
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: 3)
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: 2)
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: 3)
CrystEngComm     Full-text available via subscription   (Followers: 12)
Current Catalysis     Hybrid Journal   (Followers: 2)
Current Metabolomics     Hybrid Journal   (Followers: 5)
Current Opinion in Colloid & Interface Science     Hybrid Journal   (Followers: 9)
Current Research in Chemistry     Open Access   (Followers: 8)
Current Science     Open Access   (Followers: 58)
Dalton Transactions     Full-text available via subscription   (Followers: 22)
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: 4)
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: 2)
Environmental Chemistry     Hybrid Journal   (Followers: 8)
Environmental Chemistry Letters     Hybrid Journal   (Followers: 4)
Environmental Science & Technology Letters     Full-text available via subscription   (Followers: 5)
Environmental Science : Nano     Partially Free   (Followers: 1)
Environmental Toxicology & Chemistry     Hybrid Journal   (Followers: 17)

        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  [1577 journals]
  • Ca(II), Sr(II) and Ba(II) ion interaction with the rheumatoid arthritis
           drug tenoxicam: Structural, thermal, and biological characterization
    • Authors: Abdel Majid A. Adam
      Abstract: Recently, one of the most common conditions that manifests as joint and muscle inflammation is rheumatoid arthritis. One of the treatments for this arthritis includes non-steroidal anti-inflammatory drugs (NSAIDs) of the oxicam family, and the widest used drug in this family is tenoxicam (Tenox). In this study, the complexation properties of the drug Tenox with Ca(II), Sr(II) and Ba(II) ions in a (dichloromethane + water) binary solvent system are reported. The formed metal complexes were characterized structurally, thermally, and biologically. Tenox was found to act as a chelate monoanionic ligand towards all metal ions with complexation stoichiometry of 1:2 (Metal: Tenox) for Ca(II) and Sr(II) ions, and 1:1 for Ba(II) ions. The Tenox ligand behaves as a bidentate ligand when coordinated with Sr(II) or Ba(II) ions and as a tridentate ligand when coordinated with Ca(II) ions. The Sr(II) and Ba(II) complex of the Tenox ligand exhibited marked inhibitory effect on the cell growth of the C. albicans species.The free drug tenoxicam (Tenox) had no inhibitory activity towards the fungal strain Candida albicans. The complex of Tenox with Sr(II) ion exhibited marked inhibitory effect on the cell growth of this strain. The potency of the Sr(II)-Tenox complex is 16% greater than that of the standard drug Amphotericin B against this fungal strain.
      PubDate: 2017-09-20T06:36:10.175947-05:
      DOI: 10.1002/aoc.4055
       
  • Application of
           2-(benzyliminomethyl)-6-methoxy-4-(4-methoxyphenyl-azo)phenol in
           construction of ion-selective PVC membrane electrode for determination of
           copper (II) in mineral water sample
    • Authors: Fatemeh Pouya; Maryam Arabi, Ghodratollah Absalan
      Abstract: The potentiometric characteristics of a new Cu2+-selective electrode based on 2-(benzyliminomethyl)-6-methoxy-4-(4-methoxyphenyl-azo) phenol as an efficient ionophore has been evaluated. The effects of influential parameters on the potentiometric responses such as the amount of plasticizer, the amount of ionophore, pH of the sample solution, and the effect of coexisting ions on the electrode signal were subsequently investigated. The selectivity of the electrode was assessed by calculating the selectivity coefficients using the matched potential method. The optimum ratio of the amount of materials required for the preparation of the electrode was found to be 1.7: 32.1: 64.2: 2.0 corresponding to carboxylated PVC, dimethyl sebacate as solvent mediators, potassium tetrakis (p-chlorophenyl) borate as the anion localizing agent, and ionophore, respectively. The electrode had a fast response (7s) as well as a satisfactory Nernstian slope (29.26±0.91 mV/decade) to Cu2+ over a wide concentration range of 2.0×10−6- 5.0×10−2 M with a low detection limit of 5.9×10−7 M. The developed sensor was successfully used for the potentiometric titration of Cu2+ ion with EDTA and subsequently, efficient determination of this metal ion in a mineral water sample was performed.The efficient and accurate determination of copper (II) ions in mineral water samples is achieved when 2-(benzyliminomethyl)-6-methoxy-4-(4-methoxyphenyl-azo) phenol is used as ionophore in construction of copper (II) ion selective PVC membrane electrode. The supreme ability of the electrode as an indicator electrode for titration of Cu2+ solution with EDTA solution is also approved.
      PubDate: 2017-09-20T06:35:57.861769-05:
      DOI: 10.1002/aoc.4040
       
  • Synthesis, characterization and biological screening studies of mixed
           ligand complexes using flavonoids as precursors
    • Authors: Jeyaraman Porkodi; Natarajan Raman
      Abstract: Flavonoids are a group of plant phenolics that provide various health benefits through cell signalling pathways and antioxidant effects. In the present study, a new series of mixed ligand complexes of Co(II), Ni(II), Cu(II) and Zn(II) were synthesized by incorporating curcumin and quercetin flavonoid precursors. The structural features of the synthesized complexes were explored using elemental analysis, thermogravimetric analysis, UV–visible, infrared, NMR, mass and electron paramagnetic resonance spectral analyses and conductivity measurements. These data support an octahedral geometry of the synthesized complexes. In silico biological activity score for the ligand was predicted using PASS online software. ADMET properties were studied using VLS3D online software. Anti-inflammatory and antioxidant activities were experimentally validated which prove that theoretical predictions are in agreement with the experimental results. Interestingly the synthesized complexes interact with calf thymus DNA through groove binding mode. Moreover, they have good potential to cleave pUC19 DNA. Minimum inhibitory concentration values of the synthesized complexes reveal that they have better antimicrobial efficacy than the ligands.A new series of transition mixed ligand complexes are synthesized by incorporating curcumin and quercetin flavonoid precursors and characterized by spectral and analytical data. Based on the in silico study, the curcumin Schiff base and the metal complexes are recognized as anti-inflammatory, antioxidants and antimicrobial agents. Copper(II) complex has praiseworthy biochemical silhouette.
      PubDate: 2017-09-20T06:30:48.615261-05:
      DOI: 10.1002/aoc.4030
       
  • Preparation of magnetically recyclable ZnFe2O4 nanoparticles by easy
           single-step co-precipitation method and their catalytic performance in the
           synthesis of 2-aminothiophenes
    • Authors: N. Erfaninia; R. Tayebee, E.L. Foletto, M.M. Amini, M. Dusek, F.M. Zonoz
      Abstract: In this work, a new synthetic route for the preparation of ZnFe2O4 nanoparticles through the chemical co-precipitation using Fe2+ and Fe3+ ions in an alkaline solution was developed. The synthesized nanoparticles were characterized by XRD, FTIR, SEM, ICP-MS, DRS, TGA, VSM and elemental analysis. Characterization results confirmed the formation of single ZnFe2O4 phase, with an average particle size of 40 nm and a high saturation magnetization of 34 emu g−1. The prepared material was employed as a catalyst for the synthesis of 2-aminotiophene derivatives through the Gewald reaction. This thermally and chemically stable nanocatalyst is environmentally benign, economical and reusable which can be easily recovered using an external magnet. Therefore, it appears that this methodology can be simply extended for industrial purposes.ZnFe2O4 nanocomposite as an efficient, low-cost and environmental benign catalyst for the synthesis of substituted 2-aminothiophenes with good generality and high yields at short reaction times.
      PubDate: 2017-09-20T06:30:35.202068-05:
      DOI: 10.1002/aoc.4047
       
  • Synthesis and characterization of antibacterial chromium iron oxide
           nanoparticle-loaded activated carbon for ultrasound-assisted wastewater
           treatment
    • Authors: Ali Akbar Bazrafshan; Shaaker Hajati, Mehrorang Ghaedi, Arash Asfaram
      Abstract: The aim of this study was to evaluate the surface adsorption capacity of CrFeO3 nanoparticle-loaded activated carbon (CrFeO3-NPs–AC) for the removal of a cationic dye (methyl violet, MV). CrFeO3-NPs were hydrothermally synthesized and loaded on AC followed by characterization using X-ray diffraction, field-emission scanning electron microscopy and energy-dispersive and Fourier transform infrared spectroscopies. The CrFeO3-NPs were tested for in vitro antibacterial activities against Gram-positive (Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa) bacteria. Minimum inhibitory and minimum bactericidal concentrations of CrFeO3-NPs–AC were obtained to be 50 and 100 μg ml−1, respectively, against S. aureus and 25 and 50 μg ml−1 against P. aeruginosa. These results indicated the antibacterial properties of CrFeO3-NPs–AC. To investigate the adsorption process, several systematic experiments were designed by varying parameters such as adsorbent mass, pH, initial MV concentration and sonication time. The adsorption process was modelled and the optimal conditions were determined to be 0.013 g, 7.4, 15 mg l−1 and 8 min for adsorbent mass, pH, MV concentration and sonication time, respectively. The real experimental data were found to be efficiently explained by response surface methodology and genetic algorithm model. Kinetic studies for MV adsorption showed rapid sorption dynamics described by a second-order kinetic model, suggesting a chemisorption mechanism. Then, the experimental equilibrium data obtained at various concentrations of MV and adsorbent masses were fitted to conventional Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherm models. Dye adsorption equilibrium data were fitted well to the Langmuir isotherm. From the Langmuir model, the maximum monolayer capacity was calculated to be 65.67 mg g−1 at optimum adsorbent mass.The surface adsorption capacity of CrFeO3 nanoparticles-loaded activated carbon (CrFeO3-NPs–AC) for the removal of cationic dye (methyl violet; MV) was studied. CrFeO3-NPs were hydrothermally synthesized and loaded on activated carbon (AC) followed by their test for in-vitro antibacterial activities against gram-positive (Staphylococcus aureus) and gram-negative (Pseudomonas aeruginosa) bacteria.
      PubDate: 2017-09-20T06:27:24.255871-05:
      DOI: 10.1002/aoc.3981
       
  • Preparation, spectroscopic, thermal and powder X-ray diffraction
           characterization, and antimicrobial activities of mixed
           bis(O,O′-diisopropyldithiophosphato-S,S′)antimony(III) derivatives
           with some oxygen and sulfur donor ligands
    • Authors: Sumit Bhatiya; H.P.S. Chauhan, Nitin Carpenter
      Abstract: Newly synthesized mixed bis(O,O′-diisopropyldithiophosphato-S,S′)antimony(III) derivatives have been characterized using physicochemical, spectral, thermal and powder X-ray diffraction studies, and their antimicrobial activities were investigated. These derivatives have nanometric crystallite size (11.39–14.67 nm) with unit cell volume (4968.47 and 5079.79 Å3) and lower symmetry (monoclinic) crystal system. After thermal decomposition in inert atmosphere, these derivatives give antimony sulfide as a final decomposition product which has many potential applications, and they exhibit enhanced antimicrobial activities (greater zone of inhibition) as compared to the free ligands and standard drugs (chloroamphenicol and terbinafine were used as standard antibacterial and antifungal drugs, respectively) due to the nanometric size of the complexes.Newly synthesized bis(O,O′-diisopropyldithiophosphato-S,S′)antimony(III) derivatives have been characterized using various methods. These derivatives give antimony sulfide as a final decomposition product and exhibit enhanced antimicrobial activities (greater zone of inhibition) as compared to the free ligands and standard drugs due to the nanometric size of the complexes.
      PubDate: 2017-09-20T06:26:06.757813-05:
      DOI: 10.1002/aoc.4026
       
  • 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
      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
       
  • Fe3O4@SiO2@propyl-ANDSA: A new catalyst for the synthesis of
           tetrazoloquinazolines
    • Authors: Ramin Ghorbani-Vaghei; Sedigheh Alavinia, Narges Sarmast
      Abstract: In this paper, a mild and green protocol has been developed for the synthesis of quinazoline derivatives. The catalytic activity of 7-aminonaphthalene-1,3-disulfonic acid-functionalized magnetic Fe3O4 nanoparticles (Fe3O4@SiO2@Propyl–ANDSA) was investigated in the one-pot synthesis of new derivatives of tetrahydrotetrazolo[1,5-a]quinazolines and tetrahydrobenzo[h]tetrazolo[5,1-b]quinazolines from the reaction of aldehydes, 5-aminotetrazole, and dimedone or 6-methoxy-3,4-dihyronaphtalen-1(2H)-one at 100 °C in H2O/EtOH as the solvent. The catalyst was characterized before and after the organic reaction. Fe3O4@SiO2@Propyl–ANDSA showed remarkable advantages in comparison with previous methods. Advantages of the method presented here include easy purification, reusability of the catalyst, green and mild procedure, and synthesis of new derivatives in high yields within short reaction time.A mild and green protocol was developed for the efficient synthesis of quinazoline derivatives. The catalytic activity of 7-aminonaphthalene-1,3-disulfonic acid-functionalized magnetic Fe3O4 nanoparticles (Fe3O4@SiO2@Propyl–ANDSA) was investigated in the one-pot synthesis of new derivatives of tetrahydrotetrazolo[1,5-a]quinazolines and tetrahydrobenzo[h]tetrazolo[5,1-b]quinazolines from the reaction of aldehydes, 5-aminotetrazole, and dimedone or 6-methoxy-3,4-dihyronaphtalen-1(2H)-one. Advantages of the present method include easy purification, reusability of the catalyst, green and mild procedure, and synthesis of new derivatives in high yields within short reaction time.
      PubDate: 2017-09-20T06:21:07.884655-05:
      DOI: 10.1002/aoc.4038
       
  • Hiyama cross-coupling reaction using Pd(II) nanocatalyst immobilized on
           the surface of Fe3O4@SiO2
    • Authors: Kazem Karami; Nasrin Jamshidian, Mohammad Mehdi Nikazma, Pablo Hervés, Amir Rezaei Shahreza, Ali Karami
      Abstract: We report a simple process for the synthesis of Fe3O4@SiO2/APTMS (APTMS = 3-aminopropyltrimethoxysilane) core–shell nanocatalyst support. The new nanocatalyst was prepared by stabilization of Pd(cdha)2 (cdha = bis(2-chloro-3,4-dihydroxyacetophenone)) on the surface of the Fe3O4@SiO2/APTMS support. The structure and composition of this catalyst were characterized using various techniques. An efficient method was developed for the synthesis of a wide variety of biaryl compounds via fluoride-free Hiyama cross-coupling reactions of aryl halides with arylsiloxane, with Fe3O4@SiO2/APTMS/Pd(cdha)2 as the catalyst under reaction conditions. This methodology can be performed at 100°C through a simple one-pot operation using in situ generated palladium nanoparticles. High catalytic activity, quick separation of catalyst from products using an external magnetic field and use of water as green solvent are attributes of this protocol.A new nanocatalyst was prepared by stabilization of Pd(cdha)2 in the surface of Fe3O4@SiO2/APTMS support. High yields of products, as well as high stereoselectivity, high speed of the reaction and use of water as the solvent to additional eco-friendly attribute are important features in the fluoride-free Hiyama cross coupling reaction.
      PubDate: 2017-09-20T06:16:44.50423-05:0
      DOI: 10.1002/aoc.3978
       
  • Effect of metal complex formation on the antibacterial activity of
           nitazoxanide: Spectroscopic and density functional theory calculations
    • Authors: Ahmed M. Mansour
      Abstract: In the present work, experimental and theoretical structural studies of two new nitazoxanide (NTZ) complexes, [Co(NTZ)(NO3)2(OH2)] (1) and [Ni(NTZ)(CH3COO)(OH2)]·CH3COO (2) were reported. The susceptibility of Staphylococcus aureus and Escherichia coli towards NTZ and its complexes was assessed. NTZ behaves as a monodentate ligand via the thiazole N atom forming distorted octahedral and tetrahedral complexes with Co(II) and Ni(II) ions, respectively. The d-d transitions were assigned by the aid of time-dependent density functional theory calculations. The magnetic susceptibility value of 1 remains unchanged in the temperature range of 298–77K, while that of 2 decreases linearly with the temperature to attain 2.79 μB at 77K. Coordination of NTZ (0.084 μmol ml−1) to Co(II) (1) (0.028 μmol ml−1) and Ni(II) ions (2) (0.079 μmol ml−1) leads to an improvement in the toxicity against S. aureus.Nitazoxanide interacts with Co(II) and Ni(II) ions as a monodentate ligand via the thiazole N atom. Coordination of nitazoxanide drug (IC50 = 0.084 μmol ml−1) to Co(II) ion (1) (0.028 μmol ml−1) and Ni(II) (2) (0.079 μmol ml−1) leads to an improvement in the antibacterial activity against Staphylococcus aureus.
      PubDate: 2017-09-20T06:16:07.700618-05:
      DOI: 10.1002/aoc.4023
       
  • Green bio-based synthesis of Fe2O3@SiO2-IL/Ag hollow spheres and their
           catalytic utility for ultrasonic-assisted synthesis of propargylamines and
           benzo[b]furans
    • Authors: Samahe Sadjadi; Majid M. Heravi, Masoumeh Malmir
      Abstract: A novel magnetic hybrid system containing nano-magnetic Fe2O3 hollow spheres, silica shell, [pmim]Cl ionic liquid and silver nanoparticles was synthesized and characterized. The silver nanoparticles were prepared via biosynthesis using Achillea millefolium flower as reducing and stabilizing agent. The hybrid system was successfully used as an efficient and reusable catalyst for promoting green ultrasonic-assisted A3 and KA2 coupling reactions as well as benzo[b]furan synthesis. It was found that decoration of the magnetic core with non-magnetic moieties decreased the maximum saturation magnetization. However, the catalyst was still superparamagnetic and could be simply separated from the reaction mixture using an external magnet. The heterogeneous nature of the catalyst was also confirmed by studying its reusability and stability and the leaching of silver. Use of aqueous media, high yields, short reaction times, broad substrate tolerance and low required amount of catalyst are the merits of this protocol.A novel magnetic hybrid catalyst, h-Fe2O3@SiO2-IL/Ag, has been prepared through the synthesis of nanomagnetic Fe2O3 hollow spheres followed by coating them with silica shell, conjugation of [pmim]Cl ionic liquid and immobilization of Ag(0) nanoparticles via a biosynthetic approach. The catalytic utility of the novel catalyst for promoting green and ultrasonic-assisted synthesis of propargylamines.
      PubDate: 2017-09-20T06:14:19.816545-05:
      DOI: 10.1002/aoc.4029
       
  • Issue Information
    • Abstract: No abstract is available for this article.
      PubDate: 2017-09-20T04:04:08.849282-05:
      DOI: 10.1002/aoc.3621
       
  • Cover Image
    • Authors: Savita Beniwal; Sunil Chhimpa, Deepti Gaur, P.J. John, Yashpal Singh, Jyoti Sharma
      Abstract: The cover image, by Savita Beniwal et al., is based on the Full Paper Syntheses, characterization, antibacterial activity and molecular modelling of phenylantimony(III) heteroleptic derivatives containing substituted oximes and piperidine dithiocarbamate,
      DOI : 10.1002/aoc.3725.
      PubDate: 2017-09-20T04:04:03.015842-05:
       
  • Synthesis and structural and DNA binding studies of mono- and dinuclear
           copper(II) complexes constructed with ─O and ─N donor ligands:
           Potential anti-skin cancer drugs
    • Authors: Champaka Gurudevaru; Mohan Gopalakrishnan, Kabali Senthilkumar, Hridya Hemachandran, Ramamoorthy Siva, Thothadri Srinivasan, Devadasan Velmurugan, Swaminathan Shanmugan, Nallasamy Palanisami
      Abstract: Mononuclear and dinuclear copper(II) complexes with thiophenecarboxylic acid, [Cu(3-TCA)2(2,2′-bpy)] (1), [Cu(3-Me-2-TCA)2(H2O)(2,2′-bpy)] (2), [Cu(5-Me-2-TCA)2(H2O)(2,2′-bpy)] (3) and [Cu2(2,5-TDCA)(DMF)2(H2O)2(2,2′-bpy)2](ClO4)2 (4) (where 3-TCA = 3-thiophenecarboxylic acid; 3-Me-2-TCA = 3-methyl-2-thiophenecarboxylic acid; 5-Me-2-TCA = 5-methyl-2-thiophenecarboxylic acid; 2,5-TDCA = thiophene-2,5-dicarboxylic acid; 2,2′-bpy = 2,2′-bipyridyl; DMF = N,N-dimethylformamide), were synthesized. Compounds 1–4 were extensively characterized using both analytical and spectroscopic methods. Additionally, the solid-state structures of 1 and 4 were unambiguously established from single-crystal X-ray diffraction studies. The hexacoordinated Cu(II) centre in 1 (CuO4N2) is a distorted octahedral geometry whereas the pentacoodinated 4 (CuO3N2) has distorted square pyramidal geometry. Compounds 1 and 4 exhibit intermolecular hydrogen bonding which leads to the formation of two- and three-dimensional supramolecular architectures, respectively. Spectrophotometric and computational investigations suggest that these compounds bind with DNA in minor groove binding such that Kb = 4.9 × 105 M−1 and Ksv = 3.4 × 105 M−1, and binding score of −5.26 kcal mol−1. The binding affinity of these complexes to calf thymus DNA is in the order 2 > 3 > 4 > 1. Methyl-substituted thiophene ring increases the DNA binding affinity whereas unsubstituted thiophene ring DNA binding rate is reduced. The methyl group on the thiophene ring would sterically hinder π–π stacking of the ring with DNA base pairs, and subsequently they are involved in hydrophobic interaction with the DNA surface rather than partial intercalative interaction. Compounds 1–4 show pronounced activity against B16 mouse melanoma skin cancer cell lines as measured by MTT assay yielding IC50 values in the micromolar concentration range. The compounds could prove to be efficient anti-cancer agents, since at a concentration as low as 2.1 μg ml−1 they exerted a significant cytotoxic effect in cancer cells whereas cell viability was not affected in normal cells.Copper(II) complexes (1–4) of thiophenecarboxylic acid with 2,2′-bipydine were synthesized and characterized. Compounds 1 and 4 exhibit hydrogen bonding as well as π–π stacking interactions which lead to polymeric structures. Compounds 1–4 have strong binding activity towards calf thymus DNA. Compound 2 has better binding activity than its thiophene analogues.
      PubDate: 2017-09-15T06:30:20.026155-05:
      DOI: 10.1002/aoc.3998
       
  • Sulfonated N-heterocyclic carbine-silver (I) complexes: Synthesis,
           characterisation and biological evaluation
    • Authors: Şeyma Yaşar; Tuğba Kul Köprülü, Şaban Tekin, Sedat Yaşar
      Abstract: The synthesis, characterisation and biological activity of water-soluble Ag(I)-NHC complexes, general formula Na[(NHC)AgCl] where NHC is a sulfonated and sterically hindered N-heterocyclic carbene, is reported. The Ag-NHC complexes (2a–e) were synthesised by reacting the corresponding sulfonated NHC ligands with Ag2O in the presence of NaCl or NaBr in methanol/water (1:1) solution. Synthesised silver (I)-N-heterocyclic carbene complexes have been characterised by NMR, micro-analysis and HRMS spectroscopic methods. The IC50 values of these complexes were determined by a proliferation BrdU enzyme-linked immunosorbent assay (ELISA) against HeLa (human cervix carcinoma), HT29 (human adenocarcinoma) and L929 (mouse fibroblast) cell lines. These complexes have been highlighted as promising and original platforms for building new types of metalodrug. All new water-soluble Ag(I) complexes demonstrated remarkable cytotoxic activity against HeLa, HT29 and L929 cell lines.Synthesised silver (I)-N- heterocyclic carbene complexes have been characterised by NMR, micro- analysis and HRMS spectroscopic methods. The IC50 values of these complexes were determined by a proliferation BrdU enzyme- linked immunosorbent assay (ELISA) against HeLa (human cervix carcinoma), HT29 (human adenocarcinoma) and L929 (mouse fibroblast) cell lines. These complexes have been highlighted as promising and original platforms for building new types of metalodrug.
      PubDate: 2017-09-15T06:27:56.82438-05:0
      DOI: 10.1002/aoc.4016
       
  • Boehmite nano-particles functionalized with silylpropylamine-supported
           Keggin-type heteropolyacids: Catalysts for epoxidation of alkenes
    • Authors: Mahdi Mirzaee; Bahram Bahramian, Azam Ashrafian, Adonis Amoli
      Abstract: Boehmite nano-particles with a high degree of surface hydroxyl groups were covalently functionalized by 3-(trimethoxysilyl)-propylamine to support H3[PMo12O40], H3[PW12O40], H4[SiMo12O40] and H4[SiW12O40] Keggin-type heteropolyacids. After characterization of these catalysts by FT-IR, powder X-ray diffraction, TG/differential thermal analysis, CHN, inductively coupled plasma and transmission electron microscopy techniques, they were applied to the epoxidation of cis-cycloocten. The progress of the reactions was investigated by gas–liquid chromatography, and the catalytic procedures were optimized for the parameters involved, such as the solvent and oxidant. The results showed that 25 mg of supported H3[PMo12O40] catalyst in 1 ml C2H4Cl2 with 0.5 mmol cyclooctene and 1 mmol tert-butylhydroperoxide at reflux temperature gave 98% yield over 15 min. Recycling experiments revealed that these nanocatalysts could be repeatedly applied up to five times for a nearly complete epoxidation of cis-cycloocten. The optimized experimental conditions were also used successfully for the epoxidation of some other alkenes, such as cyclohexene, styrene and α-methyl styrene.Boehmite nano-particles were covalently functionalized by 3-trimethoxysilyl(propylamine) to support Keggin type heteropolyacids for the catalytic epoxidation of alkenes. The results showed that the supported H3PMo12O40 catalyst in C2H4Cl2 with tert-butylhydroperoxide as oxidant at reflux condition gave complete conversion in epoxidation of cis-cyclooctene over the short time of only 15 minutes. It was also successfully recycled up to five times and could be used for the epoxidation of some other alkenes, such as cyclohexene, styrene and α-methyl styrene.
      PubDate: 2017-09-15T06:26:42.221558-05:
      DOI: 10.1002/aoc.4011
       
  • Silane-bridged diphosphine ligand for palladium-catalyzed ethylene
           oligomerization
    • Authors: YongWang Huang; Wei Wei, XueJiao Meng, Le Zhang, YanHui Chen, Tao Jiang
      Abstract: In this study, bis(diphenylphosphinemethyl)dimethyl silane (L1) and its palladium(II) halide complex, L1/PdCl2 (C1), were synthesized and characterized. Single-crystal X-ray analysis of the complex revealed bidentate coordination at the Pd center. In combination with methylaluminoxane (MAO) as co-catalyst, C1 exhibited excellent catalytic activity and selectivity for ethylene dimerization toward butene. The maximum catalytic activity obtained from the C1/MAO system for ethylene dimerization to yield butenes was 7.33 × 105 g/(molPd·h). The selectivity toward butene remained stable and high (> 96%) over the various conditions.Bis(diphenylphosphinemethyl)dimethyl silane (L1) and its palladium (II) halide complex, L1/PdCl2 (C1), were synthesized and characterized. In combination with methylaluminoxane (MAO) as co-catalyst, C1 complex showed high catalytic activity and selectivity for ethylene dimerization toward butene using toluene as solvent.
      PubDate: 2017-09-15T06:16:26.502273-05:
      DOI: 10.1002/aoc.4014
       
  • Adamantyl ferrocene derivatives: Antioxidant abilities and effects on
           model lipid membranes
    • Authors: Adela Štimac; Jasmina Lapić, Valentino Blasina, Marija Lukinac, Senka Djaković, Ivo Crnolatac, Leo Frkanec, Ruža Frkanec
      Abstract: A series of homoannularly and heteroannularly substituted adamantyl ferrocene derivatives has been synthesized and their effects on membrane fluidity were investigated using liposomes as the membrane models. The liposome formulations of adamantyl ferrocene derivatives were characterized by using dynamic light scattering, differential scanning calorimetry and fluorescence anisotropy measurements. It was demonstrated that adamantyl ferrocene derivatives incorporated into the liposome significantly affect the structure of the lipid bilayer. The results of the study have revealed that adamantyl ferrocene derivatives, compounds 9–12, partition into the hydrophobic/hydrophilic interface of the membrane, causing a significant decrease in membrane fluidity. The antioxidant potential of synthesized compounds was assessed with DPPH method and it was shown that the examined compounds possess certain antioxidant activity.A series of adamantyl ferrocene derivatives has been synthesized and their effects on membrane fluidity were investigated using liposomes as the membrane models. The liposome formulations of adamantyl ferrocene derivatives were characterized and it was demonstrated that the lipid bilayes of liposome were significantly affected. The results have revealed that examined compounds, partition into the hydrophobic/hydrophilic interface of the membrane, causing a significant decrease in membrane fluidity. It was shown that the examined compounds possess certain antioxidant activity.
      PubDate: 2017-09-15T06:15:38.210848-05:
      DOI: 10.1002/aoc.4042
       
  • Covalent bonding of magnetic Fe3O4 nanoparticles to
           aminopropyl-functionalized magnesium phyllosilicate clay: Synthesis and
           cytotoxic potential investigation
    • Authors: Hasan Nasrabadi; Zahra Amirghofran, Ahmadreza Esmaeilbeig, Mehrangiz Bahrami, S. Jafar Hoseini
      Abstract: Stable water dispersion of Fe3O4 magnetic nanoparticles (NPs) were successfully synthesized by using 3-glycidoxypropyltrimethoxysilane (GPTMS) and Mg-phyllo (organo) silicate known as aminoclay (AC) containing pendant amino groups with the approximate composition (R8Si8Mg6O16(OH)4, R = CH2CH2CH2NH2). The Fe3O4-GPTMS magnetic NPs with an epoxy functional group are suitable for forming a covalent bond with the amine group of aminoclay in an epoxy ring opening reaction. Appropriate Fe3O4-GPTMS-aminoclay (FG-AC) magnetic composite are promising carriers for the targeting and delivery of platinum-based anticancer drugs. Analysis of the cytotoxicity of the nanostructures on a K562 leukemia cell line using a colorimetery assay shows that both the FG-AC and cis-platin/FG-AC magnetic composite were biocompatible. The nanostructures characterizations were investigated by Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy and energy dispersive analysis of X-ray techniques. Magnetic measurement revealed that the saturated magnetization of the FG-AC nanocomposite reached 7.6 emu/g and showed the characteristics of magnetism.An efficient method for producing stable water dispersion of magnetic Fe3O4 nanoparticles was reported which are promising carriers for the delivery of platinum-based anticancer drugs.
      PubDate: 2017-09-15T06:14:03.476112-05:
      DOI: 10.1002/aoc.4036
       
  • Isophorone-based organometallic chromophores: Synthesis, characterization
           and investigation of electro-optical properties
    • Authors: Keshvar Rahimpour; Reza Teimuri-Mofrad, Alireza Vaez
      Abstract: A series of hybrid donor–acceptor complexes with a ferrocene moiety and isophorone derivatives were synthesized. Data from 1H NMR, 13C NMR, Fourier transform infrared, atomic absorption and mass spectroscopies and CHN analysis supported the predicted structure of the products. A comparative investigation was performed using UV–visible, cyclic voltammetry and fluorescence measurements. Density functional theory was used to optimize the chromophore structure and calculation of highest occupied and lowest unoccupied molecular orbital energy levels. The ferrocene/isophorone hybrids show useful properties for further development and studies as electro-optic materials.A series of donor-acceptor complexes containing ferrocene and isophorone moieties were synthesized; 1H and 13C NMR, FT-IR, CHN analysis along with atomic absorption and mass spectroscopy supported the predicted structure of the products. Electronic and optical properties of these chromophores were studied by cyclic voltammetry, UV-Vis spectroscopy and fluorescents measurement. The quantum chemistry study was performed on synthesized compounds with the DFT approach. The B3LYP method and 6-31G (d) basis set were used for optimizing the structures in the gas-phase. The theoretical and experimental results show that these compounds can be considered as candidates in optical applications.
      PubDate: 2017-09-15T06:11:35.487392-05:
      DOI: 10.1002/aoc.4031
       
  • Sulfamic acid immobilized on amino-functionalized magnetic nanoparticles:
           A new and active magnetically recoverable catalyst for the synthesis of
           N-heterocyclic compounds
    • Authors: Lotfi Shiri; Hojatollah Narimani, Mosstafa Kazemi
      Abstract: Sulfamic acid immobilized on amino-functionalized magnetic nanoparticles (MNPs/DETA-SA) was successfully fabricated and characterized using various techniques. Diameters of approximately 15 nm for the MNPs/DETA-SA were observed from scanning electron microscopy images. The as-fabricated nanocomposite was applied as an efficient and magnetically reusable catalyst for the synthesis of 2,3-dihydroquinazoline-4(1H)-one and polyhydroquinoline derivatives. All products were obtained in good to excellent yields. Recovery tests confirm that the catalyst can be readily recovered using an external magnet and reused many times without significant loss of its catalytic activity.Sulfamic acid immobilized on amino-functionalized magnetic nanoperticles (MNPs/DETA-SA) was successfully fabricated and characterized by FT-IR, TGA, XRD, SEM and VSM spectroscopic techniques. As-fabricated nanocomposite was applied as an efficient and magnetically reusable catalyst for the synthesis of 2, 3-dihydroquinazoline-4(1H)-one and polyhydroquinoline derivatives. All products were obtained in good to excellent yields. Recovery tests confirm that the catalyst can be readily recovered by using an external magnet and reused many times without significant loss of its catalytic activity.
      PubDate: 2017-09-15T06:06:17.035271-05:
      DOI: 10.1002/aoc.3999
       
  • Co (II)-C12 alkyl carbon chain multi-functional ionic liquid immobilized
           on nano-SiO2 nano-SiO2@CoCl3-C12IL as an efficient cooperative catalyst
           for C–H activation by direct acylation of aryl halides with aldehydes
    • Authors: Yu Lin Hu; Ya Pan Wu, Ming Lu
      Abstract: Nano-silica supported ionic liquids composed of alkyl carbon chain and transition metal chlorides anions have been prepared and successfully applied as a heterogeneous catalyst in the direct aldehyde C-H activation. Catalytic results indicated that nano-SiO2 supported ionic liquid consisting C12 alkyl carbon chain and CoCl3 anion nano-SiO2@CoCl3-C12IL showed excellent catalytic properties with good to excellent yields towards the desired aryl ketones. The excellent recyclability of the supported catalyst, mild reaction conditions, low catalyst loading, and operational simplicity are the important features of this methodology.A novel and convenient procedure for the direct acylation of aryl halides with aldehydes to produce aryl ketones via the aldehyde C–H activation in the presences of nano-SiO2@CoCl3-C12IL catalyst has been developed.
      PubDate: 2017-09-15T06:01:46.550003-05:
      DOI: 10.1002/aoc.4096
       
  • Facile synthesis, characterisation and anti-inflammatory activities of
           ferrocenyl ester derivatives of 4-arylidene-5-imidazolinones
    • Authors: Dilip N. Shinde; Rajiv Trivedi, N. Vamsi Krishna, L. Giribabu, B. Sridhar, B.B. Rathod, R.S. Prakasham
      Abstract: This article describes the synthesis, optoelectronic properties and anti-inflammatory activities of a series of seven ferrocenyl ester-linked 4-arylidene-5-imidazolinone conjugates. Three different types of ortho-, meta- and para-substituted ferrocenyl esters have been prepared. Their UV–Vis spectra and electrochemical studies are described. The structure of one of the conjugates was confirmed by single-crystal X-ray diffraction study. These conjugates exhibited moderate anti-inflammatory activities.Ferrocenyl ester-linked 4-arylidene-5-imidazolinone conjugates have been synthesized and their optoelectronic and inflammatory activities are studied.
      PubDate: 2017-09-15T05:35:47.853568-05:
      DOI: 10.1002/aoc.4021
       
  • Mono- and tetranuclear copper(I) complexes with N-heterocyclic chelating
           and triphenylphosphine ligands: Crystal structures, luminescent and
           heterogeneous catalytic properties
    • Authors: Yuling Xu; Kesheng Shen, Shanshan Mao, Xinkui Shi, Huilu Wu, Xuyang Fan
      Abstract: N-heterocyclic chelating and triphenylphosphine ligands react with cuprous halide to form a variety of copper(I) complexes, namely, mononuclear [Cu(PBO)(PPh3)Br].CH2Cl2 (1) and [Cu(PBM)(PPh3)I] (2) (PBO = 2-(2′-Pyridyl)benzoxazole, PBM = 2-(2′-Pyridyl)benzimidazole, PPh3 = triphenylphosphine) and tetranuclear [Cu4(μ2-I)2(μ3-I)2(PPh3)4].2CH2Cl2 (3) have been synthesized and characterized. Complexes 1 and 2 are basically alike; both of them are mononuclear and four-coordinated, possessing a slightly distorted trigonal pyramidal geometry. Complex 3 is tetranuclear and the coordination numbers of the two copper(I) atoms are three and four, Cu(1) forming an approximate trigonal planar coordination environment, while Cu(2) is a slightly distorted trigonal pyramidal geometry, resulting in a distorted chair-like conformation. Complexes 1 and 2 are emissive in the solid state at ambient temperature, with the maxima at 552 and 602 nm, respectively, due to a MLCT excited state. Moreover, complex 3 manifests promising heterogeneous catalytic activities for the degradation of methylene blue (MB), with degradation efficiency of 99% under ambient light.Three new mono- and tetranuclear Cu(I) complexes have been synthesized and structurally characterized, which exhibit various architectures. Complexes 1 and 2 display interesting luminescent property. Complex 3 manifests promising catalytic activities for the degradation of methylene blue (MB), which degradation efficiency is 99%.
      PubDate: 2017-09-15T05:30:50.587154-05:
      DOI: 10.1002/aoc.4041
       
  • Amelioration of H4[W12SiO40] by nanomagnetic heterogenization: For the
           synthesis of 1H–pyrazolo[1,2-b]phthalazinedione derivatives
    • Authors: Priya Arora; Jaspreet Kaur Rajput
      Abstract: We conveniently coated silicotungstic acid (STA, H4[W12SiO40]) on amino-functionalized Si–magnetite nanoparticles, as surface functionalization of magnetic nanoparticles is an excellent way for green and efficient catalysis. The nanoparticles were structurally characterized using various techniques. The catalytic activity and recyclability of the STA–amine–Si–magnetite nanoparticles were probed through synthesis of 1H–pyrazolo[1,2-b]phthalazinedione derivatives. The reaction proceeds smoothly to provide products in excellent yields and short reaction times. The catalyst could be readily recovered using a simple external magnet and reused several times without any significant loss in activity. Herein, we report a comparison of the activity of H4[W12SiO40] as a homogeneous and heterogeneous catalyst, the latter being found to be more efficient. The findings offer effective methods for environmentally friendly synthesis of pyrazolo[1,2-b]phthalazinedione derivatives.The catalytic activity of a heteropoly acid i.e. silicotungstic acid has been drastically improved along with the ease of recyclability and reusability. Silicotungstic acid has been heterogenized by coating STA over amine functionalized Si-magnetite nanoparticles (STA-Amine-Si-Magnetite) and the catalytic activity has been tested by the synthesis of 1H-pyrazolo[1,2-b]phthalazinediones.
      PubDate: 2017-09-15T05:26:20.460377-05:
      DOI: 10.1002/aoc.4001
       
  • Synthesis of novel allyl palladium complexes bearing purine based NHC and
           a water soluble phosphine and their catalytic activity in the
           Suzuki-Miyaura coupling in water
    • Authors: Thomas Scattolin; Luciano Canovese, Fabiano Visentin, Stefano Paganelli, Patrizia Canton, Nicola Demitri
      Abstract: We have synthesized and fully characterized some novel allyl palladium complexes stabilized by mixed spectator ligands, namely the water soluble sodium 3,3′,3″-phosphinetriyltribenzenesulfonate, (TPPTS) and three carbenes derived from differently alkylated natural xanthines. In order to explore their potential applications we have tested their catalytic activity in the Suzuki-Miyaura coupling of para-bromoacetophenone with phenyl boronic acid, chosen as standard reaction. Only one of the complexes under study displays a remarkable stability in water and catalytic activity. We have therefore undertaken a catalytic investigation. These results are reported in the present paper together with the solid state structural characterization of a silver precursor of the palladium allyl complexes.The synthesis of three water soluble allyl palladium complexes bearing modified natural xantines and the sodium 3,3′,3″-phosphinetriyltribenzenesulfonate as spectator ligands, is reported. One among the ensuing complexes displays a reasonable catalytic activity toward the Suzuki-Miyaura reaction at moderate temperature. The catalytic study together with the solid state structure of one silver precursor is reported in the paper.
      PubDate: 2017-09-15T05:25:36.138506-05:
      DOI: 10.1002/aoc.4034
       
  • An expedient ‘click’ approach for the synthetic evaluation of
           ester-triazole-tethered organosilica conjugates
    • Authors: Gurjaspreet Singh; Sunita Rani
      Abstract: The present work articulates the synthesis of a new series of organo-functionalized triethoxysilanes derived from versatile carboxylic acids and 3-azidopropyltriethoxysilane in excellent yields. A proficient and convenient route implicating the Cu(I)-catalysed 1,3-cycloaddition of organic azide with terminal alkynes, labelled as click silylation, has been developed for the generation of ester-triazole-linked alkoxysilanyl scaffolds (4a–f). All the synthesized compounds have been thoroughly characterized using elemental analysis and Fourier transform infrared, 1H NMR and 13C NMR spectroscopic techniques. Importantly, the fabricated alkoxysilanes are potentially amenable for an in situ sol–gel condensation reaction with silica nanospheres leading to the incorporation of organic functionality via covalent grafting onto the nanostructured particle system. As a proof of concept, a one-pot preparation of organic–inorganic hybrid nanoparticles is presented using bis-silane 4 f. The efficiency and selectivity of the prepared nanocomposite towards metal ions is highlighted using adsorption experiments, and the immobilized nanoparticles present a high sensing efficiency towards Cu2+ and Pb2+ ions while demonstrating better response than that of the bulk material.New organo-functionalized triethoxysilanes (OfTES) derived from versatile carboxylic acids and 3-azidopropyltriethoxysilane (3-AzPTES) are reported. The derivatization of silica nanoparticles was carried out using one of the prepared silane to prepare organic-inorganic hybrid nanoparticles, which were utilized for the adsorptive removal of copper and lead ions.
      PubDate: 2017-09-15T05:21:30.253872-05:
      DOI: 10.1002/aoc.4028
       
  • Rhodium-catalyzed ortho-C-H olefination of aromatic aldehydes employing
           transient directing strategy
    • Authors: Xi Liu; Zhonghao Wang, Qun Chen, Ming-yang He, Liang Wang
      Abstract: A Rhodium(III)-catalyzed ortho-C-H olefination of aromatic aldehydes in the presence of catalytic amount of TsNH2 has been developed. The in situ generated imine intermediate from aldehyde and TsNH2 worked as a transient directing group. Both electron-rich and electron-deficient aromatic aldehydes were tolerated, affording the corresponding products in moderate to good yields. Importantly, the present protocol provides a straightforward access to olefinated aromatic aldehydes with aldehydes as the simple starting materials.A Rhodium(III)-catalyzed ortho-C-H olefination of aromatic aldehydes utilizing inexpensive TsNH2 as a transient directing group has been developed.
      PubDate: 2017-09-15T05:15:26.066973-05:
      DOI: 10.1002/aoc.4039
       
  • A pronounced ligand effect on platinum-catalyzed Hydrosilylation of
           terminal alkynes
    • Authors: Cheng Dong; Yang Yuan, Yu-Ming Cui, Zhan-Jiang Zheng, Jian Cao, Zheng Xu, Li-Wen Xu
      Abstract: The use of ligands to tune the reactivity and regioselectivity of transition metal-based catalyst for silicon-mediated organic synthesis (SiMOS) is an important topic and challenge in organosilicon chemistry and synthetic organic chemitstry. In this manuscript, the dual ligand platinum catalyst system was developed for the hydrosilylation of alkynes. It was found that regioselectivity enhancement was determined with combinational use of phosphine ligand (6a) and multifunctional Py-BINMOL ligand (4a). The corresponding vinylsilanes were obtained in high yields and high regioselectivities.Ligand Effect: It was found that the combinational use of multifunctional Py-BINMOL and amide-derived phosphine in platinum-catalyzed hydrosilylation of terminal alkyne could be applied in the enhancement of chemoselectivity of hydrosilylation.
      PubDate: 2017-09-15T05:10:56.971889-05:
      DOI: 10.1002/aoc.4037
       
  • Fe3O4@SiO2–ZrCl2-MNPs: A novel magnetic catalyst for the clean and
           efficient cascade synthesis of 1-(benzothiazolylamino)methyl-2-naphthol
           derivatives in the absence of solvent
    • Authors: Fatemeh Kamali; Farhad Shirini
      Abstract: A green, simple and eco-friendly three-component condensation for the synthesis of 1-(benzothiazolylamino)methyl-2-naphthols using new magnetic nanoparticles formulated as Fe3O4@SiO2–ZrCl2-MNPs is described. Considering the economic and environmental aspects, the method provides some advantages such as clean procedure, solvent-free conditions, simple operation and work-up, relatively short reaction times and high yields of the products. Moreover the introduced catalyst can be readily recovered up to 4 consecutive runs with consistent activity using an external magnet.A green, simple and eco-friendly three-component condensation for the synthesis of 1-(benzothiazolylamino)methyl-2-naphthols using new magnetic nanoparticles formulated as Fe3O4@SiO2–ZrCl2-MNPs is described.
      PubDate: 2017-09-11T03:00:44.345672-05:
      DOI: 10.1002/aoc.3972
       
  • Co(II) anchored glutaraldehyde crosslinked magnetic chitosan nanoparticles
           (MCS) for synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted
           imidazoles
    • Authors: Harminder Singh; Jaspreet Kaur Rajput
      Abstract: A simple, highly efficient and green synthesis of 2,4,5-trisubsituted and 1,2,4,5-tetrasubstituted imidazoles was developed using a novel MCS-GT@Co(II) magnetically recoverable and recyclable catalyst under refluxing conditions with ethanol as a solvent. The catalyst was prepared by immobilization of chitosan onto Fe3O4 using glutaraldehyde as crosslinker followed by Co(II) ion immobilization via cobalt acetate. The catalyst was characterized using various techniques. For organic products determination, 1H NMR, 13C NMR and Fourier transform infrared spectroscopies were used. The reaction was also tried with individual components of the catalyst, but the synergistic effect of the components in the prepared catalyst showed the highest yield and shortest reaction time.A green, novel and cost effective method of synthesis of MCS-GT-Co(II) nanoparticles is successfully developed and further they are used as a heterogeneous catalyst in the synthesis of tri and tetrasubstituted imidazoles. This method has advantages like short reaction time, high yield of product, simple work up, recyclable and reusable magnetic catalyst.
      PubDate: 2017-09-08T05:07:49.598563-05:
      DOI: 10.1002/aoc.3989
       
  • A simple, quick and novel protocol for biaryl synthesis using
           LiCl-promoted in situ-generated Pd nanoparticles
    • Authors: Parmita Phukan; Preeti Rekha Boruah, Praveen Singh Gehlot, Arvind Kumar, Diganta Sarma
      Abstract: This paper describes a simple and a very quick protocol for biaryl synthesis using the Suzuki–Miyaura cross-coupling reaction. A quintessential role of salting-out agent LiCl was observed in the Suzuki–Miyaura cross-coupling reaction that enhanced the reduction rate of Pd (II) to a considerable extent, resulting in the formation of nanosized palladium in a few seconds. The isolated Pd nanoparticles were characterized with X-ray diffraction, dynamic light scattering, TGA, transmission electron microscopy and scanning electron microscopy-dispersive X-ray spectroscopy. The Suzuki–Miyaura cross-coupling reaction proceeded very well with the in situ-generated Pd nanocatalysts furnishing the desired biaryl adducts with excellent yields.This paper describes a simple and a quick protocol for biaryl synthesis using Suzuki-Miyaura cross coupling reaction. A quintessential role of salting out agent LiCl was observed in the Suzuki-Miyaura cross-coupling reaction that enhanced the reduction rate of Pd (II) to a considerable extent affording nanosized palladium in a few seconds. The isolated Pd NPs were characterized with XRD, DLS, TGA, TEM, and SEM-EDX. Suzuki cross-coupling reaction proceeded very well with Pd-nano catalysts furnishing the desired biaryls with excellent yields.
      PubDate: 2017-09-05T23:01:31.115077-05:
      DOI: 10.1002/aoc.4009
       
  • Multifunctional triazolylferrocenyl Janus dendron: Nanoparticle
           stabilizer, smart drug carrier and supramolecular nanoreactor
    • Authors: Li Zhao; Qiangjun Ling, Xiong Liu, Chaodong Hang, Qiuxia Zhao, Fangfei Liu, Haibin Gu
      Abstract: Owing to their unique broken symmetry, amphiphilic Janus dendrimers and dendons provide fascinating properties for material, biological, pharmaceutical and biomedical applications. The integration of various organometallic moieties into these macromolecules will further offer the opportunity to form complex and intelligent architectures and materials. Here, we report a novel, simple and multifunctional Janus dendron containing redox-reversible hydrophobic ferrocene (Fc) unit, complexing-effective 1,2,3-triazole ligand and biocompatible hydrophilic triethylene glycol termini. Silver and gold nanoparticles were firstly successfully prepared by using the Janus dendron as the reducing agent of Au(III) and Ag(I), and the stabilizer of the corresponding nanoparticles. The redox response of the Fc moiety was then employed to trigger the release of model drug, rhodamine B, encapsulated in supramolecular micelles formed by the self-assembly of the Janus dendron. Finally, the precise and excellent metal-complexing ability of the triazole group in this dendron was fully utilized to stabilize a water-soluble Cu(I) catalyst, forming supramolecular nanoreactors for the catalysis of the copper(I)-catalyzed azide alkyne cycloaddition click reaction in only water. The multifunctional characteristics of this dendron highlight the potential for organometallic Janus dendrimers and dendrons in the fields of functional materials and nanomedicines.An amphiphilic triazolylferrocenyl Janus metallodendron with three PEG terminal was prepared and utilized as the reductant and stabilizer for silver and gold nanoparticles, drug carrier for redox-responsive controlled release, and supramolecular nanoreactor for copper(I)-catalyzed azide alkyne cycloaddition click reaction in only water.
      PubDate: 2017-09-05T22:56:28.473258-05:
      DOI: 10.1002/aoc.4000
       
  • Green synthesis of new pyrimido[4,5-d]pyrimidine derivatives using
           7-aminonaphthalene-1,3-disulfonic acid-functionalized magnetic Fe3O4@SiO2
           nanoparticles as catalyst
    • Authors: Ramin Ghorbani-Vaghei; Narges Sarmast
      Abstract: We, herein, describe a novel, simple, efficient and one-pot multi-component procedure for the synthesis of substituted pyrimido[4,5-d]pyrimidines via reaction of N,N-dimethyl-6-amino uracil, isothiocyanate and aromatic aldehydes promoted by 7-aminonaphthalene-1,3-disulfonic acid (ANDSA)-functionalized magnetic Fe3O4@SiO2 in water as solvent and without using any other harmful organic reagents. Compared with other reactions, using these organic–inorganic hybrid heterogeneous catalysts can help us to achieve a green procedure, high catalytic activity, easy recovery with an external magnetic field, and short reaction times.We describe a novel, efficient and one-pot multi-component procedure for the synthesis of substituted pyrimido[4,5-d]pyrimidines via reaction of N,N-dimethyl-6-amino uracil, isothiocyanate and aromatic aldehydes promoted by 7-aminonaphthalene-1,3-disulfonic acid (ANDSA)-functionalized magnetic Fe3O4@SiO2 in water as solvent and without using any other harmful organic reagents. Compared to other reactions, using these organic–inorganic hybrid heterogeneous catalysts can help us to achieve a green procedure, high catalytic activity, easy recovery and short reaction times.
      PubDate: 2017-09-05T22:55:55.085567-05:
      DOI: 10.1002/aoc.4003
       
  • Sonophotocatalytic treatment of diazinon using visible light-driven
           Ce:Cu-1,4-BDOAH2 photocatalyst in a batch-mode process: Response surface
           methodology and optimization
    • Authors: T. Taghipour; G.R. Karimipour, M. Ghaedi, M.R. Rahimi, S. Mosleh
      Abstract: Cu–1,4-benzenedioxyacetic acid (Cu-1,4-BDOAH2) with a narrow band gap (2.52 eV) was synthesized and doped with Ce to afford Ce:Cu-1,4-BDOAH2 as an efficient photocatalyst with narrower band gap (2.39 eV). The prepared Cu-1,4-BDOAH2 and Ce:Cu-1,4-BDOAH2 were characterized using Fourier transform infrared, energy-dispersive X-ray, diffuse reflectance spectroscopies, scanning electron microscopy and X-ray diffraction. The sonophotocatalytic degradation of diazinon was carried out in a batch-mode reactor using visible light-driven Ce:Cu-1,4-BDOAH2 photocatalyst as well as ultrasonic irradiation. The narrow band gap of the photocatalyst means that it can be activated under visible light illumination. The effects of operational parameters such as initial diazinon concentration (5–25 mg l−1), pH (2–10), photocatalyst dosage (10–30 mg) and irradiation time (10–30 min) on the sonophotocatalytic degradation efficiency were investigated using central composite design under response surface methodology. The optimization process was studied using desirability function and the results indicated 99.8% degradation, which was obtained at optimum values of 25 mg l−1, 6, 20 mg and 20 min for the initial concentration of diazinon, pH, photocatalyst dosage and irradiation time, respectively. Reusability experiments of Ce:Cu-1,4-BDOAH2 photocatalyst showed that it is quite stable with excellent catalytic activity even after five cycles.Cu-1,4-BDOAH2 was synthesized and doped with Ce to afford Ce:Cu-1,4-BDOAH2 as a new photocatalyst. Ce:Cu-1,4-BDOAH2 was used for sonophotocatalytic degradation of diazinon in a batch -mode reactor using visible light. The effects of operational parameters on the sonophotocatalytic degradation efficiency were investigated using central composite design under response surface methodology. The optimization process was studied using desirability function and the results indicated 99.8% degradation, which was obtained at optimal condition.
      PubDate: 2017-09-05T22:51:41.440295-05:
      DOI: 10.1002/aoc.3962
       
  • Application of the Fe3O4@1,10-phenanthroline-5,6-diol@Mn nano-catalyst for
           the green synthesis of tetrazoles and its biological performance
    • Authors: Davood Habibi; Somayyeh Heydari, Antonio Gil, Mina Afsharfarnia, Alireza Faraji, Roya Karamian, Mostafa Asadbegy
      Abstract: The Fe3O4 magnetic particles were modified with 1,10-phenanthroline-5,6-diol (Phen) and the related Mn complex (Fe3O4@Phen@Mn) synthesized as a heterogeneous catalyst to be used for the one-pot three-component synthesis of various tetrazoles. The catalysts were characterized by several methods, such as the elemental analysis, FT-IR, X-ray powder diffraction, dispersive X-ray spectroscopy, scanning electron microscopy, transmission electron microscopy, dynamic light scattering, thermogravimetric-differential thermal analysis, vibrating sample magnetometer and X-ray photoelectron spectroscopy. In addition, the antioxidant and antibacterial activities of the catalyst and its Phen ligand were in vitro screened with 2,2-diphenyl-1-picrylhydrazyl by free radical scavenging methods. Results showed that the synthesized compounds possess strong antioxidant activity (IC50; 0.172  ±  0.005 mg ml−1) as well as a good antibacterial potential in comparison to standards.The Fe3O4 magnetic particles were modified with 1,10-phenanthroline-5,6-diol and the related Mn complex synthesized as a heterogeneous catalyst to be used for the one-pot three component synthesis of various tetrazoles. The antioxidant and antibacterial activities of the catalyst and its Phen ligand were in vitro screened with 2,2-diphenyl-1-picrylhydrazyl (DPPH) by free radical scavenging methods. Results showed that the synthesized compounds possess strong antioxidant activity (IC50; 0.172 ± 0.005mg/ml) as well as a good antibacterial potential in comparison to standards.
      PubDate: 2017-09-05T22:46:21.967534-05:
      DOI: 10.1002/aoc.4005
       
  • Preparation and characterization of hexamethylenetetramine-functionalized
           magnetic nanoparticles and their application as novel catalyst for the
           synthesis of pyranopyrazole derivatives
    • Authors: Ramin Ghorbani-Vaghei; Vida Izadkhah
      Abstract: A new magnetic catalyst was prepared through the reaction of silanol groups, on the surface of silica-coated Fe3O4 magnetic nanoparticles, with (3-chloropropyl)triethoxysilane followed by hexamethylenetetramine and chlorosulfonic acid. The obtained magnetic catalyst was characterized using thermogravimetric analysis, vibrating sample magnetometry, scanning electron microscopy and energy-dispersive X-ray analysis. Its catalytic activity was investigated in the synthesis of pyranopyrazole compounds, and the results were excellent regarding high yield of the products and short reaction time.A new silica coated Fe3O4 MNPs was prepared and then functionalized with hexamethylenetetramine and chlorosulfonic acid. Then its catalytic activity was investigated in the synthesis of pyranopyrazole compounds.
      PubDate: 2017-09-05T22:46:10.162086-05:
      DOI: 10.1002/aoc.4025
       
  • DNA fastening and scission actions of Cu(II), Co(II), Ni(II) and Zn(II)
           complexes: synthesis, spectral characterization and cytotoxic study
    • Authors: Ganesan Kumaravel; Ponnukalai Ponya Utthra, Natarajan Raman
      Abstract: A heterocyclic compound, 2-(aminomethyl)benzimidazole dihydrohydrochloride, was treated with nitrobenzaldehyde to form a Schiff base that was made to react with divalent metals. A co-ligand, either 1,10-phenanthroline or 2,2′-bipyridine, was added to this mixture to obtain metal chelators of type [ML(co-L)2]Cl2. They were in 1:1:2 stoichiometry ratio, which was characterized by various spectroscopic techniques that suggested an octahedral geometry around the central metal ions. These complexes were investigated for their binding affinities with calf thymus (CT) DNA, using various techniques, such as UV–Vis, viscosity, cyclic voltammetry (CV), etc. The binding interaction studies revealed intercalation as the possible binding mode of the complexes with the CT DNA. In addition, these complexes were screened for their antimicrobial potential and DNA denaturing tendencies using gel electrophoretic assay. The antimicrobial screening investigation showed that the complexes behaved as better antimicrobial agents than the ligand, especially, complex 5 shows exceptional activity even in the electrophoretic assay along with the antimicrobial efficacy. Moreover, complex 5 was able to denature the plasmid DNA better than the other compounds. All the compounds were screened for cytotoxic efficacy, and the IC50 values suggest that the compounds possess cytotoxic activity to some extent that is almost the same as the activity of cisplatin.The DNA interactions exhibited by eight novel complexes, obtained from the Schiff base ligand [2-(aminomethyl)benzimidazole dihydrohydrochloride with nitrobenzaldehyde], metal salts and a coligand, either 1,10-phenanthroline or 2,2′-bipyridine, suggest that they are good metallointercalators. The binding interaction studies revealed intercalation as the possible binding mode of the complexes with the CT DNA. Their various characteristics were explored where the complexes manifested as excellent antimicrobial agents. The IC50 values suggest that the synthesized compounds possess almost same cytotoxic activity compared to cisplatin.
      PubDate: 2017-09-05T22:41:05.900549-05:
      DOI: 10.1002/aoc.4010
       
  • Tungstate supported mesoporous silica SBA-15 with imidazolium framework as
           a hybrid nanocatalyst for selective oxidation of sulfides in the presence
           of hydrogen peroxide
    • Authors: Alireza Sedrpoushan; Fereshteh Hosseini-Eshbala, Farajollah Mohanazadeh, Masoud Heydari
      Abstract: In this work, a new heterogeneous catalyst (SBA-15/Im/WO42−) was prepared, and then its performance in the oxidation of organic sulfides was studied (using 30% H2O2 as green oxidant under neutral reaction conditions). This organic–inorganic hybrid mesoporous material was characterized by various techniques, such as FT-IR, inductively coupled plasma, X-ray powder diffraction, high-resolution-transmission electron microscopy, N2 adsorption–desorption and thermogravimetric analysis. The catalyst was also applied to the selective oxidation of various sulfides. The hybrid catalyst was easily recovered, and was very stable and retained good activity for at least five successive runs without any additional activation. Moreover, there was no remarkable decrease in the activity and selectivity of the catalyst. The products could be easily isolated by just removing the solvent after filtering the catalyst. The yields of the catalytic productions through this catalyst were in the range from 75% to 97%.A new heterogeneous catalyst (SBA-15/Im/WO42−) was prepared and then, its performance for the oxidation of organic sulfides was studied (using 30% H2O2 as green oxidant under neutral reaction conditions). The hybrid catalyst was easily recovered and been very stable, and retained good activity for at least 5 successive runs without any additional activation. The products could be easily isolated by just removing the solvent after filtering the catalyst.
      PubDate: 2017-08-31T06:27:23.689196-05:
      DOI: 10.1002/aoc.4004
       
  • Iminophosphine palladium catalysts for Suzuki carbonylative coupling
           reaction
    • Authors: Mustafa Kemal Yılmaz; Hülya Keleş, Simay İnce, Mustafa Keleş
      Abstract: Three iminophosphine ligands having soft phosphorus and hard nitrogen atoms and their Pd(II) complexes were synthesized and characterized using 1H NMR, 13C NMR, 31P NMR and Fourier transform infrared spectroscopic techniques. Also, electrochemical properties of the iminophosphines and their Pd(II) complexes were investigated in acetonitrile–tetrabutylammonium perchlorate solution with cyclic and square wave voltammetry techniques. All Pd(II) complexes were evaluated as catalysts for carbonylative cross-coupling reactions of aryl iodides with phenylboronic acid. The Suzuki carbonylation of aryl iodides at 80 °C under balloon pressure of carbon monoxide in the presence of K2CO3 as a base was examined, and good to high conversions and excellent selectivities were obtained.Three iminophosphine ligands and their Pd(II) complexes were synthesized and characterized. Electrochemical properties of the iminophosphines and their Pd(II) complexes were investigated in acetonitrile–tetrabutylammonium perchlorate solution with cyclic and square wave voltammetry techniques. All Pd(II) complexes were evaluated as catalysts for carbonylative coupling reactions of aryl iodides with phenylboronic acid at 80 °C under balloon pressure of carbon monoxide in the presence of K2CO3 as a base and good to high conversions and excellent selectivities were obtained.
      PubDate: 2017-08-31T06:21:18.330939-05:
      DOI: 10.1002/aoc.4002
       
  • Preparation of an organic–inorganic hybrid based on synergy of Brønsted
           and Lewis acid centres as heterogeneous magnetic nanocatalyst for
           ultrafast synthesis of acetaminophen
    • Authors: M. Kooti; E. Nasiri
      Abstract: A heterogeneous nanocatalyst based on a Cu(II) complex containing phosphotungstic acid and N/O-donor ligands supported on cobalt ferrite nanoparticles was successfully prepared. The synthesized nanocatalyst was characterized using various techniques. The magnetic nanocatalyst was examined as an efficient and synergistic catalyst for ultrafast synthesis of acetaminophen at room temperature and under solventless conditions. The examined synergistic nanocatalyst, which has both Lewis and Brønsted acidic sites, could be easily separated from the reaction system and reused several times without significant loss of its activity. The synthesized acetaminophen was also fully characterized.A novel copper complex with phosphotungstic acid and N/O donor ligands was supported on cobalt ferrite NPs and used as efficient catalyst for ultrafast synthesis of acetaminophen. Both the catalyst and acetaminophen have been fully ccharacterized.The nanocatalyst could be easily recovered and reused for several times without loss of its activity.
      PubDate: 2017-08-31T06:17:19.926032-05:
      DOI: 10.1002/aoc.3990
       
  • Synthesis of pyranopyrazoles using
           nano-Fe-[phenylsalicylaldiminemethylpyranopyrazole]Cl2 as a new Schiff
           base complex and catalyst
    • Authors: Ahmad Reza Moosavi-Zare; Hamid Goudarziafshar, Khadijeh Saki
      Abstract: By the condensation reaction of benzaldehyde with ethyl acetoacetate, malononitrile and hydrazine hydrate in the presence of FeCl2, a pyranopyrazole derivative was prepared which was then reacted with salicylaldehyde to afford nano-Fe-[phenylsalicylaldiminemethylpyranopyrazole]Cl2 (nano-[Fe-PSMP]Cl2). The prepared nano-Schiff base complex was fully characterized using Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, differential thermogravimetry, scanning electron microscopy and UV–visible spectroscopy, and was used as an efficient and catalyst for the preparation of pyranopyrazoles.Nano-Fe-[phenyl-salicylaldimine-methylpyranopyrazole]Cl2 as a new nano-Schiff base complex and catalyst was prepared, identified and applied for the preparation of pyranopyrazoles.
      PubDate: 2017-08-25T06:20:45.297416-05:
      DOI: 10.1002/aoc.3968
       
  • A tridentate CNO-donor palladium(II) complex as efficient catalyst for
           direct C―H arylation: Application in preparation of imidazole-based
           push–pull chromophores
    • Authors: Hui-Hong Li; Ratnava Maitra, Ya-Ting Kuo, Jie-Hong Chen, Ching-Han Hu, Hon Man Lee
      Abstract: A series of imidazolium chlorides for the formation of tridentate CNO-donor palladium(II) complexes featuring N-heterocyclic carbene moieties have been developed from cheap and readily available starting materials with high yields. Their palladium complexes were prepared by reactions between the ligand precursors and PdCl2 using K2CO3 as base in pyridine with reasonable yields. These air-stable metal complexes were characterized using 1H NMR and 13C{1H} NMR spectroscopy and elemental analyses. Heteronuclear multiple bond correlation experiments were performed to identify key NMR signals of these compounds. The structures of two of the complexes were also established by single-crystal X-ray diffraction analysis. One of these complexes was successfully applied in the direct C―H functionalization reactions between heterocyclic compounds and aryl bromides, producing excellent yields of coupled products. The coupling reactions were scalable, allowing grams of coupled products to be obtained with a mere 2 mol% of Pd loading. The catalyst system developed allowed the large-scale preparation of several push–pull chromophores straightforwardly. Photophysical properties based on UV–visible and fluorescence spectroscopy for these chromophores were investigated. Deep blue photoluminescence with moderate quantum efficiency and twisted intramolecular charge transfer excited state were observed for these chromophores. Density functional theory (DFT) and time-dependent DFT calculations were performed to support the experimental results.A tridentate CNO-donor palladium(II) complex featuring an N-heterocyclic carbene moiety was developed as an efficient catalyst for direct C―H arylation between heterocyclic compounds and aryl bromides. The catalyst system allowed large-scale preparation of several push–pull chromophores straightforwardly with a mere 2 mol% of Pd loading.
      PubDate: 2017-08-25T05:32:15.586936-05:
      DOI: 10.1002/aoc.3956
       
  • Selective detection of Hg2+ ion in aqueous medium with the use of
           3-(pyrimidin-2-ylimino)indolin-2-one-functionalized SBA-15
    • Authors: Negar Lashgari; Alireza Badiei, Ghodsi Mohammadi Ziarani
      Abstract: An isatin-based fluorophore, 3-(pyrimidin-2-ylimino)indolin-2-one, was grafted on a large-pore mesoporous silica material (SBA-15) via a two-step modification process. The obtained material (SBA-Is-Py) was characterized using various techniques and the characterization showed that the ordered porous structure was preserved after the post-grafting procedure. The optical sensing ability of SBA-Is-Py was studied upon the addition of a variety of metal ions and a marked fluorescence quenching by Hg2+ ion was observed. SBA-Is-Py exhibited excellent Hg2+-specific luminescence quenching over various competing cations. Furthermore, linear changes of the optical properties of SBA-Is-Py as a function of the concentrations of Hg2+ ion were found, with a calculated detection limit of 3.28 × 10−7 M. In addition, SBA-Is-Py was successfully employed for the determination of Hg2+ in real water samples.An isatin based fluorophore, (3-(pyrimidin-2-ylimino)indolin-2-one), was grafted on a mesoporous silica material (SBA-15) via a two-step modification process. The optical sensing ability of SBA-Is-Py was studied upon the addition of a variety of metal ions and a remarkable fluorescence quenching by Hg2+ ion was observed. SBA-Is-Py exhibited excellent Hg2+-specific luminescence quenching over various competitive cations. Furthermore, linear changes of the optical properties of SBA-Is-Py as a function of the concentrations of Hg2+ ion were proved.
      PubDate: 2017-08-25T05:21:39.004327-05:
      DOI: 10.1002/aoc.3991
       
  • Synthesis, characterization and electrocatalytic performance of a
           dinuclear triazenidosilver(I) complex for hydrogen production
    • Authors: Dan Xue; Su-Ping Luo, Shu-Zhong Zhan
      Abstract: Our group has developed a series of molecular electrocatalysts for hydrogen generation based on triazenido–metal complexes (cobalt, copper, etc.). In this paper, we first present the electrocatalytic performance of a new dinuclear silver complex, [Ag2(L)2], formed by the reaction of the triazenido ligand 1-[(2-carboxymethyl)benzene]-3-[(2-methoxy)benzene]triazene (HL) with AgNO3. At room temperature, the silver complex shows photoluminescence at 653 nm. The electrocatalytic systems based on this silver complex can afford 106.57 and 1536.36 moles of hydrogen per mole of catalyst per hour from acetic acid at an overpotential (OP) of 991.6 mV and from a neutral aqueous buffer (pH = 7.0) at an OP of 837.6 mV, respectively. Electrochemical investigations show that both silver ion and triazenido ligand play a role in determining the catalytic activities of the electrocatalytic system.The reaction of 1-[(2-carboxymethyl)benzene]-3-[(2-methoxy)benzene]triazene (HL) with AgNO3 affords a silver complex, [Ag2(L)2], a new electrocatalyst for hydrogen evolution from both acetic acid and water.
      PubDate: 2017-08-25T05:17:21.842298-05:
      DOI: 10.1002/aoc.3997
       
  • Ferrocene-tagged ionic liquid stabilized on silica-coated magnetic
           nanoparticles: Efficient catalyst for the synthesis of
           2-amino-3-cyano-4H-pyran derivatives under solvent-free conditions
    • Authors: Reza Teimuri-Mofrad; Mahdi Gholamhosseini-Nazari, Elmira Payami, Somayeh Esmati
      Abstract: An advanced novel magnetic ionic liquid based on imidazolium tagged with ferrocene, a supported ionic liquid, is introduced as a recyclable heterogeneous catalyst. Catalytic activity of the novel nanocatalyst was investigated in one-pot three-component reactions of various aldehydes, malononitrile and 2-naphthol for the facile synthesis of 2-amino-3-cyano-4H-pyran derivatives under solvent-free conditions without additional co-catalyst or additive in air. For this purpose, we firstly synthesized and investigated 1-(4-ferrocenylbutyl)-3-methylimidazolium acetate, [FcBuMeIm][OAc], as a novel basic ferrocene-tagged ionic liquid. This ferrocene-tagged ionic liquid was then linked to silica-coated nano-Fe3O4 to afford a novel heterogeneous magnetic nanocatalyst, namely [Fe3O4@SiO2@Im-Fc][OAc]. The synthesized novel catalyst was characterized using 1H NMR, 13C NMR, Fourier transform infrared and energy-dispersive X-ray spectroscopies, X-ray diffraction, and transmission and field emission scanning electron microscopies. Combination of some unique characteristics of ferrocene and the supported ionic liquid developed the catalytic activity in a simple, efficient, green and eco-friendly protocol. The catalyst could be reused several times without loss of activity.An advanced novel magnetic ionic liquid based on imidazolium tagged with ferrocene was designed and synthesized as a recyclable heterogeneous catalyst. The activity of the nanocatalyst was investigated for the facile synthesis of 2-amino-3-cyano-4H-pyran derivatives under solvent-free conditions.
      PubDate: 2017-08-25T05:15:55.189493-05:
      DOI: 10.1002/aoc.3955
       
  • Nitro group reduction and Suzuki reaction catalysed by palladium supported
           on magnetic nanoparticles modified with carbon quantum dots generated from
           glycerol and urea
    • Authors: Mohammad Gholinejad; Fatemeh Zareh, Carmen Nájera
      Abstract: Glycerol and urea were used as green and cheap sources of carbon quantum dots (CQD) for modifying Fe3O4 nanoparticles (NPs). The obtained CQD@Fe3O4 NPs were used for the stabilization of palladium species and the prepared catalyst, Pd@CQD@Fe3O4, was characterized using various techniques. This magnetic supported palladium was applied as an efficient catalyst for the reduction of aromatic nitro compounds to primary amines at room temperature using very low palladium loading (0.008 mol%) and also for the Suzuki–Miyaura cross-coupling reaction of aryl halides as well as challenging heteroaryl bromides and aryl diazonium salts with arylboronic acids and with potassium phenyltrifluoroborate. This magnetically recyclable catalyst was recovered and reused for seven consecutive runs in the reduction of 4-nitrotoluene to p-toluidine and for ten consecutive runs in the reaction of 4-iodoanisole with phenylboronic acid with small decrease of activity. The catalyst reused in the Suzuki reaction was characterized using transmission electron microscopy, vibrating sample magnetometry and X-ray photoelectron spectroscopy. Using experiments such as hot filtration and poisoning tests, it has been shown that the true catalyst works under homogeneous conditions according to the release–return pathway of active palladium species.A new sustainable magnetic carbon quantum dot-supported palladium catalyst was prepared and applied in reduction and Suzuki reactions.
      PubDate: 2017-08-25T05:11:46.819238-05:
      DOI: 10.1002/aoc.3984
       
  • Suzuki–Miyaura coupling reaction in water in the presence of robust
           palladium immobilized on modified magnetic Fe3O4 nanoparticles as a
           recoverable catalyst
    • Authors: Arefeh Dadras; M. Reza Naimi-Jamal, Firouz Matloubi Moghaddam, Seyed Ebrahim Ayati
      Abstract: Aryl halides and especially inactive aryl chlorides were coupled to benzenoid aromatic rings in a Suzuki–Miyaura coupling reaction in the absence of organic solvents and toxic phosphine ligands. The reaction was catalysed by a recoverable magnetic nanocatalyst, Pd@Fe3O4, in aqueous media. This method is green, and the catalyst is easily removed from the reaction media using an external magnetic field and can be re-used at least 10 times without any considerable loss in its activity. The catalyst was characterized using scanning and transmission electron microscopies, thermogravimetric analysis, inductively coupled plasma spectroscopy, Fourier transform infrared spectroscopy, CHN analysis, X-ray diffraction and vibrating sample magnetometry.Biaryl compounds were synthesized in water as a green medium via Suzuki–Miyaura coupling reaction of aryl halides and phenylboronic acid using palladium immobilized on modified Fe3O4 magnetic nanoparticles. The catalyst can be easily separated from reaction media and is useable for more than 10 times without reduction in its activity.
      PubDate: 2017-08-25T05:05:53.38195-05:0
      DOI: 10.1002/aoc.3993
       
  • Application of novel copper organic material for facile microextraction of
           sodium valproate from human plasma samples: Experimental design
           optimization and isotherm study
    • Authors: Sonia Bahrani; Mehrorang Ghaedi, Tahere Taghipour, Mohammad Javad Khoshnood Mansoorkhani, Ahmad Reza Bagheri, Abbas Ostovan
      Abstract: Well-designed metal organic materials (MOMs) were synthesized and applied for pre-concentration and determination of sodium valproate (Na-VP) from biological samples, bound to the copper complex of 1,4-phenylenedioxydiacetic acid under mild conditions. The channels of this sorbent provide high efficiency and also selectivity. The MOMs were structurally characterized using Fourier transform infrared and energy-dispersive X-ray spectroscopies, scanning electron microscopy and X-ray diffraction, and they were found to have suitable features for quantification of Na-VP using HPLC coupled with UV detection at λ = 215 nm. Moreover, the rate of adsorption is improved by ultrasonic power and the experimental data are best fitted according to Freundlich adsorption isotherm. According to the central composite design, the best experimental conditions are 280.0 μl, 3.0 min and 17.0 mg for volume of eluent, sonication time and sorbent mass respectively. Calibration plots show linear responses towards Na-VP concentrations (0.4–18.0 μg ml−1), satisfactory limit of detection (0.06 μg ml−1, S/N = 3) and reasonable enrichment factor (70.58). The coefficient of variation values of both inter- and intra-day analyses were less than 4.0%, indicating a candidate method for the determination of Na-VP in human plasma with reasonable recovery and efficiency.Well-designed metal organic materials (MOMs) were synthesized and applied for pre-concentration and determination of sodium valproate (Na-VP) from biological samples, bound to the copper complex of 1,4-phenylenedioxydiacetic acid under mild conditions. The channels of this sorbent provide high efficiency and also selectivity.
      PubDate: 2017-08-25T05:00:41.624639-05:
      DOI: 10.1002/aoc.3960
       
  • Preparation of Fe3O4@5,10-dihydropyrido[2,3-b]quinoxaline-7,8-diol copper
           complex: A capable nanocatalyst for the green synthesis of 1-substituted
           1H-tetrazoles
    • Authors: Davood Habibi; Narges Pakravan, Ameneh Arabi, Zahra Kaboudvand
      Abstract: Fe3O4 magnetic nanoparticles functionalized with 5,10-dihydropyrido[2,3-b]quinoxaline-7,8-diol were synthesized as was their complex with copper as a novel nanomagnetic iron oxide catalyst via a simple and green method, and characterized using various techniques. The capability of the catalyst was evaluated in the one-pot three-component synthesis of different tetrazoles, which showed very good results. Mild reaction conditions, good reusability and simple magnetic work-up make this methodology interesting for the efficient synthesis of tetrazoles.Fe3O4 magnetic nanoparticles functionalized with 5,10-dihydropyrido[2,3-b] quinoxaline-7,8-diol were synthesized as was their complex with copper as a novel nanomagnetic iron oxide catalyst via a simple and green method. The capability of the catalyst was evaluatedin the one-pot three-component synthesis of different tetrazoles, which showed very good results.
      PubDate: 2017-08-25T04:55:54.842524-05:
      DOI: 10.1002/aoc.3988
       
  • Synthesis, crystal structures and DNA/human serum albumin binding of
           ternary Cu(II) complexes containing amino acids and
           6-(pyrazin-2-yl)-1,3,5-triazine-2,4-diamino
    • Authors: Chun-Lian Zhang; Xue-Mei Zhang, Wei Liu, Shi Chen, Zong-Wan Mao, Xue-Yi Le
      Abstract: Two water-soluble 6-(pyrazin-2-yl)-1,3,5-triazine-2,4-diamino (pzta)-based Cu(II) complexes, namely [Cu(l-Val)(pzta)(H2O)]ClO4 (1) and [Cu(l-Thr)(pzta)(H2O)]ClO4 (2) (l-Val: l-valinate; l-Thr: l-threoninate), were synthesized and characterized using elemental analyses, molar conductance measurements, spectroscopic methods and single-crystal X-ray diffraction. The results indicated that the molecular structures of the complexes are five-coordinated and show a distorted square-pyramidal geometry, in which the central copper ions are coordinated to N,N atoms of pzta and N,O atoms of amino acids. The interactions of the complexes with DNA were investigated using electronic absorption, competitive fluorescence titration, circular dichroism and viscosity measurements. These studies confirmed that the complexes bind to DNA through a groove binding mode with certain affinities (Kb = 4.71 × 103 and 1.98 × 103 M−1 for 1 and 2, respectively). The human serum albumin (HSA) binding properties of the complexes were also evaluated using fluorescence and synchronous fluorescence spectroscopies, indicating that the complexes could quench the intrinsic fluorescence of HSA in a static quenching process. The relevant thermodynamic parameters revealed the involvement of van der Waals forces and hydrogen bonds in the formation of complex–HSA systems. Finally, molecular docking technology was also used to further verify the interactions of the complexes with DNA/HSA.6-(Pyrazin-2-yl)-1,3,5-triazine-2,4-diamino (pzta)-based Cu(II) complexes with amino acids, [Cu(l-Val)(pzta)(H2O)]ClO4 (1) and [Cu(l-Thr)(pzta)(H2O)]ClO4 (2), were synthesized. The DNA/human serum albumin (HSA) binding properties of the complexes were explored using spectroscopic and viscometric measurement methods, and the binding modes or sites were further confirmed using molecular docking technology.
      PubDate: 2017-08-22T04:33:08.525963-05:
      DOI: 10.1002/aoc.3994
       
  • Facile fabrication of ZnO/N-doped helical carbon nanotubes composites with
           enhanced photocatalytic activity toward organic pollutant degradation
    • Authors: Shuaishuai Ma; Qing Li, Zhilan Cai, Zhaolian Ye, Yuming Zhou
      Abstract: Novel ZnO/N-doped helical carbon nanotubes (ZnO/N-HCNTs) composites were successfully synthesized via a facile chemical precipitation approach at room temperature. The sample was well characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM) and ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS). The photocatalytic activity was evaluated in the degradation of methylene blue (MB) aqueous solution under UV light irradiation. It is found that ZnO nanoparticles were highly and uniformly anchored on the surface and inner tubes of the N-HCNTs with size of about 5 nm, and significantly enhanced the photocatalytic activity compared to pure ZnO. The enhanced photocatalytic activity of ZnO/N-HCNTs composites can be ascribed to the integrative synergistic effect of effective interfacial hybridization between N-HCNTs and ZnO nanoparticles and the prolonged lifetime of photogenerated electron–hole pairs. Moreover, the ZnO/N-HCNTs could be easily recycled without any obvious decrease in photocatalytic activity and could be promote their application in the area of environmental remediation.Novel ZnO/N-doped helical carbon nanotubes (ZnO/N-HCNTs) composites were successfully synthesized via a facile chemical precipitation approach at room temperature. It is found that ZnO nanoparticles were highly and uniformly anchored on the surface and inner tubes of the N-HCNTs with size of about 5 nm, and significantly enhanced the photocatalytic activity compared to pure ZnO.
      PubDate: 2017-08-22T04:31:56.537994-05:
      DOI: 10.1002/aoc.3966
       
  • Novel ionic liquid supported on Fe3O4 nanoparticles as an efficient
           catalyst for the synthesis of new chromenes
    • Authors: Javad Safaei-Ghomi; Fahime Eshteghal, Hossein Shahbazi-Alavi
      Abstract: An efficient procedure for the synthesis of new chromenes by the multicomponent reaction of aldehydes, 4-hydroxycoumarin and 2-hydroxynaphthalene-1,4-dione in the presence of an ionic liquid supported on Fe3O4 nanoparticles is described. The ionic liquid supported on Fe3O4 nanoparticles as a magnetic catalyst gives products in high yields. Significant features of this method are: short reaction times, excellent yields, green method and use of an effective catalyst that can be recovered and reused many times without loss of its catalytic activity.A novel ionic liquid (IL) supported on Fe3O4 magnetic nanoparticles (MNPs) has been successfully prepared and characterized. These MNPs were used as an efficient heterogeneous catalyst for the one-pot three-component synthesis of new chromenes in ethanol–water at 50 °C.
      PubDate: 2017-08-22T04:31:32.629377-05:
      DOI: 10.1002/aoc.3987
       
  • Excellent alkene epoxidation catalytic activity of macrocyclic-based
           complex of dioxo-Mo(VI) on supermagnetic separable nanocatalyst
    • Authors: Fatemeh Payami; Abolfazl Bezaatpour, Habibollah Eskandari
      Abstract: A phenoxybutane-based Schiff base complex of cis-dioxo-Mo(VI) was supported on paramagnetic nanoparticles and characterized using powder X-ray diffraction, infrared, diffuse reflectance and atomic absorption spectroscopies, scanning and transmission electron microscopies and vibrating sample magnetometry. The separable nanocatalyst was tested for the selective epoxidation of cyclohexene, cyclooctene, styrene, indene, α-pinene, 1-octene, 1-heptene, 1-dodecene and trans-stilbene using tert-butyl hydroperoxide (80% in di-tert-butyl peroxide–water, 3:2) as oxidant in chloroform. The catalyst was efficient for oxidation of cyclooctene with 100% selectivity for epoxidation with 98% conversion in 10 min. We were able to separate magnetically the nanocatalyst using an external magnetic field and used the catalyst at least six successive times without significant decrease in conversion. The turnover frequency of the catalyst was remarkable (2556 h−1 for cyclooctene). The proposed nanomagnetic catalyst has advantages in terms of catalytic activity, selectivity, catalytic reaction time and reusability by easy separation.Phenoxy butane based Schiff base complex of Cis-dioxo-Mo(VI) was supported on nanoparticles and characterized by physico-chemical spectroscopy. The catalyst was tested for the selective epoxidation of olefins using TBHP in chloroform. This catalyst is efficient for oxidation of cyclooctene with 100% selectivity for epoxidation with 98% conversion in 10 min. The turn over frequency of catalyst is so remarkable (2556 h−1 for cyclooctene).
      PubDate: 2017-08-22T04:25:53.747807-05:
      DOI: 10.1002/aoc.3986
       
  • Chemo-selective reduction of nitro and nitrile compounds using Ni
           nanoparticles immobilized on hyperbranched polymer-functionalized magnetic
           nanoparticles
    • Authors: Seyed Jamal Tabatabaei Rezaei; Asemeh Mashhadi Malekzadeh, Sima Poulaei, Ali Ramazani, Hossein Khorramabadi
      Abstract: The nitro and nitrile groups in aromatic and aliphatic compounds containing various reducible substituents such as carboxylic acid, ketone, aldehyde and halogen are selectively reduced to the corresponding amines in water as a green solvent with excellent yields by employing NaBH4 in the presence of Fe3O4@PAMAM/Ni(0)-b-PEG nanocatalyst. The morphology and structural features of the catalyst were characterized using various microscopic and spectroscopic techniques. The designed catalyst system because of it being covered with hydrophilic polymers is soluble in a wide range of solvents (e.g. water and ethanol) and suitable for immobilizing and stabilizing Ni nanoparticles in aqueous mediums. In addition, the catalyst can be easily recovered from a reaction mixture by applying an external magnetic field and can be reused up to six runs without significant loss of activity.We have developed a novel magnetically recoverable nickel-based semi-heterogeneous catalytic system (Fe3O4@PAMAM/Ni(0)-b-PEG) for the selective reduction of nitro and nitrile groups in aromatic and aliphatic compounds containing various reducible substituents to the corresponding amines in water as a green solvent.
      PubDate: 2017-08-22T04:20:48.122997-05:
      DOI: 10.1002/aoc.3975
       
  • Porphyrin-based polymer-supported palladium as an excellent and recyclable
           catalyst for Suzuki–Miyaura coupling reaction in water
    • Authors: Jian Chen; Ju Zhang, Dajian Zhu, Tao Li
      Abstract: A porphyrin-based polymer with high surface area was synthesized using 5,10,15,20-tetraphenylporphyrin through a one-pot Friedel–Crafts alkylation reaction. Pd(II) was successfully supported on this polymer. This strategy provides an easy approach to produce highly stable Pd–porphyrin-based polymer. The resulting Pd catalyst was characterized using Fourier transform infrared and X-ray photoelectron spectroscopies, thermogravimetric analysis, scanning and transmission electron microscopies and N2 adsorption–desorption measurements. This porphyrin-based polymer-supported Pd was used as a heterogeneous catalyst for Suzuki–Miyaura coupling reaction in water. The results demonstrated that this Pd catalyst indeed exhibited excellent catalytic activity and recycling performance in water, even for inactive aryl chloride substrate. A new heterogeneous strategy for catalyzing the Suzuki–Miyaura reaction in water is provided.A porphyrin-based polymer-supported Pd catalyst is reported for Suzuki–Miyaura coupling reactions in water.
      PubDate: 2017-08-22T04:16:43.435479-05:
      DOI: 10.1002/aoc.3996
       
  • Copper containing nanosilica thioalated dendritic material: A recyclable
           catalyst for synthesis of benzimidazoles and benzothiazoles
    • Authors: Maryam Zakeri; Majid Moghadam, Valiollah Mirkhani, Shahram Tangestaninejad, Iraj Mohammadpoor-Baltork, Zari Pahlevanneshan
      Abstract: In this paper, the design and characterization of a new heterogeneous catalyst by incorporation of copper ions into the nanosilica modified by thiole–based dendrimer are reported. The prepared catalyst was characterized by FT–IR, TGA, elemental analysis, FE–SEM, TEM, XPS and ICP–OES techniques. This material was used as catalyst in the synthesis benzimidazoles and benzothiazoles by the reaction of substituted benzaldehydes with 1,2–diaminobenzene or 2–aminothiophenol, respectively. The advantages of the present catalytic system are high yields, mild conditions and short reaction times. On the other hand, this new synthesized catalyst was recycled very well and reused several times without significant loss of its catalytic activity.The synthesis and characterization of Cu(II) containing thiolated dendrimer on nanosilica have been described. The prepared catalyst was characterized by FT-IR, UV–Vis, TGA, elemental analysis, ICP-OES, TEM, FE-SEM and XPS techniques. The Cu(II)-TD@nSiO2 has been used as an efficient catalyst for the preparation of various benzimidazoles and benzothiazoles under mild conditions. Furthermore, the catalyst is stable under the reaction conditions and can be recycled and reused several times without a significant loss in activity.
      PubDate: 2017-08-22T04:15:41.044032-05:
      DOI: 10.1002/aoc.3937
       
  • Highly efficient oxidative cleavage of alkenes and cyanosilylation of
           aldehydes catalysed by magnetically recoverable MIL-101
    • Authors: Maryam Nourian; Farnaz Zadehahmadi, Reihaneh Kardanpour, Shahram Tangestaninejad, Majid Moghadam, Valiollah Mirkhani, Iraj Mohammadpoor-Baltork
      Abstract: The catalytic activity of magnetically recoverable MIL-101 was investigated in the oxidation of alkenes to carboxylic acids and cyanosilylation of aldehydes. MIL-101 was treated with Fe3O4 and the prepared catalyst was characterized using Fourier transform infrared spectroscopy, X-ray diffraction, N2 adsorption measurements, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy and inductively coupled plasma analysis. The catalytic active sites in this heterogeneous catalyst are Cr3+ nodes of the MIL-101 framework. This heterogeneous catalyst has the advantages of excellent yields, short reaction times and reusability several times without significant decrease in its initial activity and stability in both oxidation and cyanosilylation reactions. Its magnetic property allows its easy separation using an external magnetic field.Magnetically recoverable catalysts are of great interest. In this paper, the catalytic activity of magnetically recoverable MIL-101 was investigated in the oxidation of alkenes to carboxylic acids and cyanosilylation of aldehydes.
      PubDate: 2017-08-22T04:10:55.051425-05:
      DOI: 10.1002/aoc.3957
       
  • Oxidation reactions catalysed by molybdenum(VI) complexes grafted on
           UiO-66 metal–organic framework as an elegant nanoreactor
    • Authors: Niloufar Afzali; Shahram Tangestaninejad, Majid Moghadam, Valiollah Mirkhani, Adam Mechler, Iraj Mohammadpoor-Baltork, Reihaneh Kardanpour, Farnaz Zadehahmadi
      Abstract: A heterogeneous catalyst was synthesized by immobilizing Mo(CO)3 in a UiO-66 metal–organic framework. The benzene ring of the organic linker in UiO-66 was modified via liquid-phase deposition of molybdenum hexacarbonyl, Mo(CO)6, as starting precursor to form the (arene)Mo(CO)3 species inside the framework. The structure of this catalyst was characterized using X-ray diffraction, and chemical integrity was confirmed using Fourier transform infrared and diffuse reflectance UV–visible spectroscopic methods. The metal content was analysed with inductively coupled plasma. Field emission scanning electron microscopy was used to measure particle size and N2 adsorption measurements to characterize the specific surface area. This catalytic system was efficiently applied for epoxidation of alkenes and oxidation of sulfides. The Mo-containing metal–organic framework was reused several times without any appreciable loss of its efficiency.We have developed an eco-friendly solid catalyst by immobilization of Mo complex into the framework of UiO-66 following a post-synthetic modification strategy. The benzene ring of the organic linker in UiO-66 was modified with Mo(CO)3 species. The prepared catalyst was totally characterized and efficiently applied for epoxidation of alkenes and oxidation of sulfides.
      PubDate: 2017-08-22T04:10:44.82014-05:0
      DOI: 10.1002/aoc.3958
       
  • Polystyrene-supported Pd(II)–N-heterocyclic carbene complex as a
           heterogeneous and recyclable precatalyst for cross-coupling of acyl
           chlorides with arylboronic acids
    • Authors: Barahman Movassagh; Fatemeh Hajizadeh, Elmira Mohammadi
      Abstract: Palladium-catalysed cross-coupling reaction of aroyl chlorides with arylboronic acids was achieved in the presence of polystyrene-supported palladium(II)–N-heterocyclic carbene complex, using K2CO3 in acetone–water, providing diaryl ketones in high yields. Furthermore, the heterogeneous catalyst could be reused up to four times without significant loss of activity.PS-NHC-Pd(II) was used in the Suzuki–Miyaura cross-coupling of aroyl chlorides and arylboronic acids to produce a wide range of diaryl ketones. This heterogeneous catalyst exhibited high efficiency in aqueous media under mild reaction conditions. It was recycled for four successive runs without any significant loss in its activity.
      PubDate: 2017-08-15T03:01:35.205682-05:
      DOI: 10.1002/aoc.3982
       
  • Utilization of industrial waste as a novel adsorbent: Mono/competitive
           adsorption of chromium(VI) and nickel(II) using diatomite waste modified
           by EDTA
    • Authors: Haitao Sha; Yunhai Wu, Yiang Fan
      Abstract: The adsorption of Cr(VI) and Ni(II) using ethylenediaminetetraacetic acid-modified diatomite waste (EDTA-DW) as an adsorbent in single and binary systems was investigated. The EDTA-DW was characterized using various analytical techniques, including Fourier transform infrared spectroscopy, thermogravimetric analysis, Brunauer–Emmett–Teller measurements, X-ray diffraction, scanning electron microscopy and energy-dispersive spectrometry. The adsorption experiment was conducted by varying pH, adsorbent dosage, initial concentration and temperature. In the single system, the sorption data for Cr(VI) fitted the Langmuir isotherm, but the Ni(II) adsorption data fitted well the Freundlich isotherm. The maximum sorption capacity of Cr(VI) and Ni(II) was 2.9 mg g−1 at pH = 3 and 3.64 mg g−1 at pH = 8, respectively. The kinetic data for both Cr(VI) and Ni(II) followed well the pseudo-second-order kinetic model in single and binary systems. Meanwhile, the extended Langmuir and extended Freundlich multicomponent isotherm models were found to fit the competitive adsorption data for Cr(VI) and Ni(II). In addition, in the binary system, the existence of Ni(II) hindered the adsorption of Cr(VI), but the presence of Cr(VI) enhanced the removal of Ni(II). This study provides some realistic and valid data about the usage of modified diatomite waste for the removal of metal ions.The aim was to recycle diatomite waste into a novel adsorbent. To improve adsorption capacity, EDTA was chosen to modify the diatomite waste. The physical and chemical properties of the surface of the adsorbent could be demonstrated by a series of representations. The novel adsorbent shows different adsorption capacities between single system and binary system for Cr(VI) and Ni(II).
      PubDate: 2017-08-15T03:01:31.717777-05:
      DOI: 10.1002/aoc.3977
       
  • Palladium(II) complexes bearing N-alkylpiperidoimidazolin-2-ylidene
           derivatives: Effect of alkyl chain length of ligands on catalytic activity
           
    • Authors: Sinem Çakır; Gülşah Türkmen, Hayati Türkmen
      Abstract: A series of piperidoimidazolinium salts which differ in the chain lengths (butyl, octyl, dodecyl, octadecyl) and their Pd–N-heterocyclic carbene complexes with pyridine were synthesized and characterized using elemental analysis and spectroscopic methods. The effects of these ligands on catalyst activation and the performance of the complexes were studied in Suzuki–Miyaura reactions of arylboronic acid with aryl chlorides. The complex with the ligand having the longest chain length was found to be most active. The results demonstrated that the length of the alkyl chain of the piperidoimidazolin-2-ylidene controlled the dispersion and composition of the nanoparticles and it affected the catalytic activity. The impact of alkyl chain length of piperidoimidazolin-2-ylidene on the Suzuki–Miyaura reactions of arylboronic acid with aryl halides was systematically investigated.Pd-PEPPSI-NHC complexes with various chain lengths were prepared and characterized. The catalytic activities of the complexes in Suzuki–Miyaura C–C coupling reactions were investigated and compared. The aliphatic chain length of the complexes affects the dispersion and composition of the nanoparticles.
      PubDate: 2017-08-15T02:55:48.856972-05:
      DOI: 10.1002/aoc.3969
       
  • Some divalent metal(II) complexes of novel potentially tetradentate Schiff
           base N,N′-bis(2-carboxyphenylimine)-2,5-thiophenedicarboxaldhyde:
           Synthesis, spectroscopic characterization and bioactivities
    • Authors: Ayman A. Abdel Aziz; Ibrahim S.A. El-Sayed, Mostafa M.H. Khalil
      Abstract: A novel tetradentate dianionic Schiff base ligand, N,N′-bis(2-carboxyphenylimine)-2,5-thiophenedicarboxaldhyde (H2L) and some first row d-transition metal chelates (Co(II), Cu(II), Ni(II) and Zn(II)) were synthesized and characterized using various physicochemical and spectroscopic methods. The spectroscopic data suggested that the parent Schiff base ligand coordinates through both deprotonated carboxylic oxygen and imine nitrogen atoms. The free Schiff base and its metal chelates were screened for their antimicrobial activities for various pathogenic bacteria and fungi using the agar well diffusion method. The antibacterial and antifungal activities of all the newly synthesized compounds are significant compared to the standard drugs ciprofloxacin and nystatin. The antioxidant activities of the compounds were determined by reduction of 1,1-diphenyl-2-picrylhydrazyl and compared with that of vitamin C as a standard. DNA binding ability of the novel Schiff base and its complexes was investigated using absorption spectroscopy, fluorescence spectroscopy, viscosity measurements and thermal denaturation. The obtained results clearly demonstrate that the binding affinity with calf thymus DNA follows the order: Cu(II) complex > Ni(II) complex > Zn(II) complex > Co(II) complex >H2L. Furthermore, the DNA cleavage activity of the newly synthesized ligand and its metal complexes was investigated using supercoiled plasmid DNA (pUC18) gel electrophoresis.Novel mononuclear, four coordinated Co(II), Ni(II), Cu(II) and Zn(II) complexes were synthesized via thermal reaction of their metal acetate salts with the novel tetradentate Schiff base N,N′-(1-carboxyphenylimine)-2,5-thiophenedicarboxaldhyde. Investigation of antioxidation properties, binding with calf thymus DNA and DNA cleavage properties of the novel compounds suggested possible utilization of novel compounds for pharmaceutical applications.
      PubDate: 2017-03-27T04:37:15.079758-05:
      DOI: 10.1002/aoc.3730
       
  • Density functional theory/B3LYP study of nanometric
           4-(2,4-dihydroxy-5-formylphen-1-ylazo)-N-(4-methylpyrimidin-2-yl)benzenesulfonamide
           complexes: Quantitative structure–activity relationship, docking,
           spectral and biological investigations
    • Authors: Fawaz A. Saad; Marwa G. Elghalban, Nashwa M. El-Metwaly, Hoda El-Ghamry, Abdalla M. Khedr
      Abstract: New metal ion complexes were isolated after coupling with 4-(2,4-dihydroxy-5-formylphen-1-ylazo)-N-(4-methylpyrimidin-2-yl)benzenesulfonamide (H2L) drug ligand. The structural and molecular formulae of drug derivative and its complexes were elucidated using spectral, analytical and theoretical tools. Vibrational spectral data proved that H2L behaves as a monobasic bidentate ligand through one nitrogen from azo group and ionized hydroxyl oxygen towards all metal ions. UV–visible and magnetic moment measurements indicated that Fe(III), Cr(III), Mn(II) and Ni(II) complexes have octahedral configuration whereas Cd(II), Zn(II) and Co(II) complexes are in tetrahedral form. The Cu(II)complex has square planar geometry as verified through electron spin resonance essential parameters. X-ray diffraction data indicated the amorphous nature of all compounds with no regular arrangement for the solid constituents during the precipitation process. Transmission electron microscopy images showed homogeneous metal ion distribution on the surface of the complexes with nanometric particles. Coats–Redfern equations were applied for calculating thermo-kinetic parameters for suitable thermal decomposition stages. Gaussian09 and quantitative structure–activity relationship modelling studies were used to verify the structural and biological features. Docking study using microorganism protein receptors was implemented to throw light on the biological behaviour of the proposed drug. The investigated ligand and metal complexes were screened for their in vitro antimicrobial activities against fungal and bacterial strains. The resulting data indicated that the investigated compounds are highly promising bactericides and fungicides. The antitumour activities of all compounds were evaluated towards human liver carcinoma (HEPG2) cell line.Optimized structure of 4-(2,4-dihydroxy-5-formylphen-1-ylazo)-N-(4-methylpyrimidin-2-yl)benzenesulfonamide (H2L)
      PubDate: 2017-03-20T02:36:30.985366-05:
      DOI: 10.1002/aoc.3721
       
  • Synthesis, characterization and biological activities of two novel
           orthopalladated complexes: Interactions with DNA and bovine serum albumin,
           antitumour activity and molecular docking studies
    • Authors: Kazem Karami; Sara Hashemi, Janusz Lipkowski, Fatemeh Mardani, Amir Abbas Momtazi-borojeni, Zohreh Mehri Lighvan
      Abstract: [Pd(L1)(C,N)]CF3SO3 and [Pd(L2)(C,N)]CF3SO3 (L1 = 2,2′-bipyridine, L2 = 1,10-phenanthroline and C,N = benzylamine) novel orthopalladated complexes have been synthesized and characterized using various techniques. The binding of the complexes with native calf thymus DNA (CT-DNA) was monitored using UV–visible absorption spectrophotometry, fluorescence spectroscopy and thermal denaturation studies. Our results indicate that these complexes can strongly bind to CT-DNA via partial intercalative mode. In addition, fluorescence spectrometry of bovine serum albumin (BSA) with the complexes shows that the fluorescence quenching mechanism of BSA is a static process. The results of site-competitive replacement experiments with specific site markers clearly indicate that the complexes bind to site I of BSA. Notably, the complexes exhibit significant in vitro cytotoxicity against two human cancer cell lines (Jurkat and MCF-7) with IC50 values varying from 37 to 53 μM. Finally, a molecular docking experiment effectively proves the binding of the Pd(II) complexes to DNA and BSA.Two new orthopalladated complexes have been synthesized and characterized by various techniques. The compounds can bind to CT-DNA via partial intercalative mode. Fluorescence spectrometry of BSA with the complexes shows that the fluorescence quenching mechanism of BSA is a static process. The complexes exhibit significant in vitro cytotoxicity against two human cancer cell lines (Jurkat and MCF-7). A molecular docking experiment effectively proves the binding of the Pd(II) complexes to DNA and BSA.
      PubDate: 2017-03-20T02:26:15.190949-05:
      DOI: 10.1002/aoc.3740
       
  • Water-soluble Schiff base Cu(II) and Zn(II) complexes: Synthesis, DNA
           targeting ability and chemotherapeutic potential of Cu(II) complex for
           hepatocellular carcinoma – in vitro and in vivo approach
    • Authors: Narayanaperumal Pravin; Ganesan Kumaravel, Raju Senthilkumar, Natarajan Raman
      Abstract: Reliable compounds with low toxicity are tempting potential chemotherapeutics. With an aim of achieving less toxic but more potent metallodrugs, four new-generation hydrophilic Cu(II) and Zn(II) complexes with DNA-targeting properties were synthesized and characterized using various physicochemical data. The excellent DNA binding and cleavage results confirmed the mode of binding of DNA with the complexes and their ability to denature it. The profound in vitro cytotoxicity exhibited by complex 3 against a panel of cell lines (HeLa, MCF-7 and HepG-2) along with NHDF (normal human dermal fibroblasts) with distinct activity towards HepG-2 and low toxicity to NHDF prompted in vivo studies of induced hepatocellular carcinoma-affected Swiss albino rats. On evaluating various serum hepatic, biological and histopathological parameters, complex 3 showed excellent activity in restoring the damaged liver to normal. As a means of identifying the pathway of DNA damage, flow cytometric evaluation of cell cycle analysis was performed, which revealed S phase arrest-induced apoptosis in HepG-2 cells by complex 3, making it a cell cycle-specific drug.Reliable compounds with low toxicity are tempting potential chemotherapeutics. To achieve less toxic but more potent metallodrugs, four new hydrophilic Cu(II) and Zn(II) complexes with DNA-targeting properties were synthesized and characterized. The binding and cleavage results confirmed the mode of binding of DNA with the complexes and their ability to denature it.
      PubDate: 2017-02-22T06:11:00.679759-05:
      DOI: 10.1002/aoc.3739
       
  • Synthesis of retinoid analogues of juvenile hormones
    • Authors: Lotfi Doumandji; Hubert Matondo, Sébastien Estaran, Boudjema Hamada, Christophe Lagneau, James Devillers, André Yébakima, Annick Doucet-Panaye, Jean-Pierre Doucet, Armand Lattes
      Abstract: As part of a collaborative research project aimed at designing new chemicals active on mosquito larvae, we sought accessible raw materials and an efficient synthesis method for preparing large amounts of active substances. For this we selected retinoic acid, which has functionality close to that of juvenile hormones. From this molecule we developed ester and trifluoromethyl ketone synthesis that was fast and led to good yields.The synthesis of the target molecule was conducted using a two-step procedure. Firstly, the corresponding acyl chloride was prepared by reacting trans-retinoic acid with thionyl chloride in anhydrous dichloromethane in the presence of pyridine as catalyst. The second step was a trifluoromethylation the acyl chloride with trifluoromethylcopper, which showed better responsiveness.
      PubDate: 2017-02-20T01:20:29.806862-05:
      DOI: 10.1002/aoc.3736
       
  • Synthesis and characterization of iron- and nitrogen-functionalized
           graphene catalysts for oxygen reduction reaction
    • Authors: Rapidah Othman; Md. Sohrab Hossain, Noor H. Jabarullah
      Abstract: Iron- and nitrogen-functionalized graphene (Fe-N-G), as well as iron- and nitrogen-functionalized oxidized graphene (Fe-N-Gox) catalysts were synthesized as non-noble metal electrocatalysts for oxygen reduction reaction (ORR). The physical properties of the resultant catalysts were characterized using nitrogen adsorption measurements, X-ray diffraction, Raman and X-ray photoelectron spectroscopies and transmission electron microscopy. Subsequently, ORR activities of the catalysts were determined electrochemically using a conventional three-electrode cell via cyclic voltammetry with a rotating disc electrode, the results of which indicated that the synthesized catalysts had a marked electrocatalytic activity towards ORR in acid media. Among the synthesized catalysts, that functionalized using 2,4,6-tris(2-pyridyl)-1,3,5-triazine as nitrogen source had the highest electrocatalytic activity with the highest onset potential (0.98 V/SHE) and limiting current density (5.12 mA cm−2). The findings are particularly important to determine a non-precious metal catalyst for ORR activity in fuel cells.Iron- and nitrogen-doped graphene catalyst with incorporation of nitrogen using 2,4,6-tris(2-pyridyl)-1,3,5-triazine. (a) High-resolution N 1 s XPS spectrum; (b) TEM image (resolution: 100 nm); (c) oxygen reduction reaction curves in oxygen-saturated 0.5 M H2SO4 at a scan rate of 1 mV s−1.
      PubDate: 2017-02-16T20:55:49.78414-05:0
      DOI: 10.1002/aoc.3738
       
  • Effect of lipophilicity of wingtip groups on the anticancer potential of
           mono N-heterocyclic carbene silver(I) complexes: Synthesis, crystal
           structures and in vitro anticancer study
    • Authors: Tabinda Fatima; Rosenani A. Haque, Mohd R. Razali, Ashfaq Ahmad, Muhammad Asif, Mohamed B. Khadeer Ahamed, A. M. S. Abdul Majid
      Abstract: A series of symmetrically n-alkyl-substituted mono benzimidazolium salts with steady increase in n-alkyl chain length have been prepared by stepwise N-alkylation resulting in salts (1–8). The mono N-heterocyclic carbene (NHC)–Ag(I) complexes (9–16) derived from the respective salts were readily accessible by in situ deprotonation using Ag2O. All the salts and the complexes were characterized using Fourier transform infrared, 1H NMR, 13C NMR and elemental analyses. Furthermore, the structures of salts 3 and 7 and complex 16 were elucidated using X-ray crystallography, which established that this mono NHC–Ag(I) complex has a linear bis-carbene arrangement (C2–Ag). The proligands and the respective Ag(I) complexes were studied for their in vitro anticancer potential against human colon cancer cell line (HCT-116) using 5-fluorouracil as a standard. From the IC50 values of all the tested compounds, it can be postulated that there is an influential relationship between the increase in chain length of the wingtip n-alkyl groups and the anticancer potential. The proligands 4–8 and their respective complexes 12–16 with long n-alkyl chain lengths (n = 6–10) showed better IC50 values (0.3–3.9 μM) than the standard drug with the complexes displaying markedly better antiproliferation activity against HCT-116 cell line than the respective proligands and the standard drug (IC50 = 10.2 μM).A series of symmetrically n-alkyl-substituted mono benzimidazolium salts and their corresponding N-heterocyclic carbene silver(I) complexes were synthesized and studied for their in vitro anticancer activity against HCT-116 cells. The anticancer activity was enhanced on increasing the n-alkyl chain length.
      PubDate: 2017-02-16T20:45:39.936514-05:
      DOI: 10.1002/aoc.3735
       
  • Carbon nanospheres with well-controlled nano-morphologies as support for
           palladium-catalyzed Suzuki coupling reaction
    • Authors: Wenhuan Dong; Saisai Cheng, Cheng Feng, Ningzhao Shang, Shutao Gao, Chun Wang, Zhi Wang
      Abstract: Uniform carbon nanospheres (UCS) with well-controlled nano-morphologies were fabricated by hydrothermal carbonization of sucrose in the presence of kayexalate. Highly dispersed and ultrafine palladium nanoparticles were supported on the UCS through a facile co-reduction process with NaBH4 as reducing agent. The obtained Pd@UCS exhibited efficient catalytic activity for the Suzuki coupling reaction. Moreover, the as-prepared catalyst could be recycled and reused at least five times without significant loss of its catalytic activity.With the help of kayexalate, uniform carbon nanospheres (UCS) were prepared by hydrothermal carbonization of an easily obtained biomass source – sucrose. UCS were activated under air condition at 800 °C. Highly dispersed and ultrafine Pd nanoparticles were immobilized on the UCS using NaBH4 solution at room temperature. The final catalyst exhibited good catalytic performance for Suzuki coupling reactions.
      PubDate: 2017-02-15T20:50:34.116544-05:
      DOI: 10.1002/aoc.3741
       
  • Inorganic–organic hybrid chitosan-based Schiff base–Ni complex as a
           novel, highly efficient and recyclable heterogeneous catalyst for
           synthesis of pyrazolophthalazinediones
    • Authors: Hossein Naeimi; Sepideh Lahouti
      Abstract: A Schiff base based on chitosan was synthesized through treatment of chitosan and p-dimethylaminobenzaldehyde in methanol solution. This biopolymeric Schiff base was used to prepare a new first row transition metal complex of Ni(II). The biopolymeric Schiff base and the synthesized tetra-coordinated complex were characterized using Fourier transform infrared, 1H NMR and 13C NMR techniques. Then, an efficient synthetic method for functionalized 1H–pyrazolo[1,2-b]phthalazine-5,10-diones was successfully developed using one-pot domino reaction of ninhydrin and malononitrile with 3-arylamino-5,5-dimethyl-2-cyclohexenones catalysed by the chitosan-based Schiff base complex of Ni(II) at room temperature. The advantages of this protocol are easy work-up, short reaction times and high yield of products and also the catalyst can be readily isolated from the reaction mixture and recycled without loss of catalytic activity.Chitosan Schiff base complex of Ni (II) as low toxicity, easy preparation, recyclable catalyst for the synthesis of 1H-pyrazolo [1,2-b] phthalazine-5,10-diones in ethanol was reported.
      PubDate: 2017-02-15T03:25:35.172781-05:
      DOI: 10.1002/aoc.3732
       
  • Synthesis and characterization of metal complexes of azo dye based on
           5-nitro-8-hydroxyquinoline and their applications in dyeing polyester
           fabrics
    • Authors: Nadia A. El-Wakiel; Hala F. Rizk, Seham A. Ibrahim
      Abstract: New Mn(II), Ni(II), Co(II) and Cu(II) complexes of an azo dye ligand based on p-phenylenediamine with 5-nitro-8-hydroxyquinoline were synthesized and characterized using elemental analysis, inductive coupled plasma analysis, molar conductance, powder X-ray diffraction, thermogravimetric analysis, magnetic moment measurements, and infrared, 1H NMR, electron ionization mass and UV–visible spectral studies. The spectral and analytical data reveal that the azo dye ligand acts as a monobasic bidentate ligand via deprotonated OH and nitrogen atom of the quinoline ring. The data support the formulation of all complexes with a 2:1 ligand-to-metal ratio, except the Mn(II) complex that has a mononuclear formula. All complexes have an octahedral structure. The molar conductance data reveal that all the metal complexes are non-electrolytic in nature. From the X-ray data, the average particle size of the ligand and its complexes is 0.32–0.64 nm. The colour fastness to light, washing, perspiration, sublimation and rubbing of the prepared ligand and its complexes on polyester fabrics and colorimetric properties were measured. The results reveal that the ligand and its complexes have a good to moderate affinity to polyester fibres.New Mn(II), Ni(II), Co(II) and Cu(II) complexes of an azo dye ligand were synthesized. Spectral and analytical data revealed that the azo dye ligand acts as a monobasic bidentate ligand. X-ray data for the investigated compounds were obtained. The colour fastness of the prepared ligand and its complexes on polyester fabrics and colorimetric properties were measured.
      PubDate: 2017-02-14T21:55:47.799015-05:
      DOI: 10.1002/aoc.3723
       
  • Synthesis, characterization, and biological and anticancer studies of
           mixed ligand complexes with Schiff base and 2,2′-bipyridine
    • Authors: M.M. Omar; Hanan F. Abd El-Halim, Eman A.M. Khalil
      Abstract: New mixed ligand complexes of transition metals were synthesized from a Schiff base (L1) obtained by the condensation reaction of oxamide and furfural as primary ligand and 2,2′-bipyridine (L2) as secondary ligand. The ligands and their metal complexes were studied using various spectroscopic methods. Also thermal analyses were conducted. The mixed ligand complexes were found to have formulae [M(L1)(L2)]Clm⋅nH2O (M = Cr(III) and Fe(III): m = 3, n = 0; M = Cu(II) and Cd(II): m = 2, n = 1; M = Mn(II), Co(II), Ni(II) and Zn(II): m = 2, n = 0). The resultant data revealed that the metal complexes have octahedral structure. Also, the mixed ligand complexes are electrolytic. The biological and anticancer activities of the new compounds were tested against breast cancer (MCF-7) and colon cancer (HCT-116) cell lines. The results showed high activity for the synthesized compounds.Anticancer activities of Schiff base ligand and its mixed ligand complexes for MCF-7 cell line (breast cancer). A new Schiff base ligand and its transition metal mixed ligand complexes were prepared and characterized using various spectral and physicochemical methods. The biological and anticancer activities of the compounds were also investigated.
      PubDate: 2017-02-10T00:50:50.368016-05:
      DOI: 10.1002/aoc.3724
       
  • Tin powder-promoted diastereoselective allylation of chiral acylhydrazones
    • Authors: Xiansha Peng; Ke-Hu Wang, Danfeng Huang, Juanjuan Wang, Yalin Wang, Yingpeng Su, Yulai Hu, Ying Fu
      Abstract: An efficient method for the allylation of chiral acylhydrazones derived from aldehydes has been developed to give the corresponding allylic hydrazides in good yields and diastereoselectivities. The method uses a combination of tin powder and allylic bromide as allylation system, which avoids the use of toxic allylic stannanes while retaining their merits.An efficient method for the allylation of chiral acylhydrazones derived from aldehydes has been developed to give the corresponding allylic hydrazides in good yields and diastereoselectivities. The method uses a combination of tin powder and allylic bromide as allylation system, which avoids the use of toxic allylic stannanes while retaining their merits.
      PubDate: 2017-02-09T19:55:27.833081-05:
      DOI: 10.1002/aoc.3731
       
  • A highly reactive and magnetic recyclable catalyst based on silver
           nanoparticles supported on ferrite for N-monoalkylation of amines with
           alcohols
    • Authors: Ahmad Bayat; Mehdi Shakourian-Fard, Peyman Nouri, Mohammad Mahmoodi Hashemi
      Abstract: Fe3O4@SiO2-Ag catalyst was found to be highly active and selective in the N-alkylation of amines with a variety of aromatic and linear alcohols. The heterogeneous nature of the Fe3O4@SiO2-Ag catalyst allows easy recovery and regeneration by applying an external magnet for six subsequent reaction cycles. The prepared catalyst was characterized using electron microscopy techniques, X-ray diffraction, vibrating sample magnetometry and atomic absorption spectroscopy.A heterogeneous silver catalyst was synthesized for N-alkylation of amines with alcohols. The catalyst can be easily recovered by applying an external magnetic field and used for six reaction cycles without considerable loss of activity. The attractive features of this procedure are excellent yields and operational simplicity.
      PubDate: 2017-02-09T19:50:33.905023-05:
      DOI: 10.1002/aoc.3720
       
  • Synthesis, characterization and catalytic application of a new
           organometallic oligomer based on polyhedral oligomeric silsesquioxane
    • Authors: Eduardo Guimarães Vieira; Rafael Oliveira Silva, Enes Furlani Junior, Newton Luiz Dias Filho
      Abstract: Although homogeneous catalysts provide high performance and selectivity, the difficulty of separation and recycling of these catalysts has bothered the scientific community worldwide. Therefore, the demand for heterogeneous catalysts that possess the advantages of homogeneous ones, with ease of separation and recyclability remains a topic of major impact. The oligomeric catalyst synthesized in this work was characterized using elemental analysis, Fourier transform infrared, 13C NMR, 29Si NMR and energy-dispersive X-ray spectroscopies, X-ray diffraction, thermogravimetric analysis, scanning electron microscopy and Brunauer–Emmett–Teller analysis and compared to its homogeneous counterpart [W(CO)3Br2(ATC)] in the epoxidation of 1-octene, cyclooctene, (S)-limonene, cis-3-hexen-1-ol, trans-3-hexen-1-ol and styrene. The results showed that the percentage conversion for the homogeneous species [W(CO)3Br2(ATC)] was slightly higher than for the oligomeric catalyst (POSS-ATC-[W(CO)3Br2]). Furthermore, the selectivity for epoxide of the oligomeric catalyst was greater than that of the homogeneous catalyst by about 25% when (S)-limonene was used. Great conversions (yields) of products were obtained with a wide range of substrates and the catalyst was recycled many times without any substantial loss of its catalytic activity.A new organometallic oligomer catalyst was synthesized from 3-chloropropyltriethoxysilane via a hydrolytic condensation reaction. The catalyst showed very good catalytic activity in the epoxidation of 1-octene, cyclooctene, (S)-limonene, cis-3-hexen-1-ol, trans-3-hexen-1-ol and styrene in the presence of tert-butyl hydroperoxide as oxidant and high selectivity after being used for at least five cycles.
      PubDate: 2017-02-06T21:40:33.422972-05:
      DOI: 10.1002/aoc.3722
       
  • Facile fabrication of magnetic MoO2–Salen-modified graphene-based
           catalyst for epoxidation of alkenes
    • Authors: Zhifang Li; Changlong Yang, Yuanyuan Ma, Peng Li, Jingqi Guan, Qiubin Kan
      Abstract: A facile, green and efficient method for the immobilization of MoO2–Salen onto graphene hybridized with glucose-coated magnetic Fe3O4 nanoparticles is proposed to fabricate a magnetic organic–inorganic hybrid heterogeneous RGO/Fe3O4@C-Salen-MoO2 catalyst for the epoxidation of cyclooctene and geraniol using tert-butyl hydroperoxide or H2O2 as oxidant. Carbon-coated Fe3O4 can improve the stability and add functional ─OH groups on the surface of Fe3O4. The fabricated composite exhibited good performance due to good dispersion of MoO2–Salen active sites. The catalyst can be easily separated from the reaction system using a permanent magnet and used three times without significantly losing its catalytic activity and selectivity.A magnetic organic–inorganic hybrid heterogeneous RGO/Fe3O4@C-Salen-MoO2 catalyst was synthesized using a facile and green method. It demonstrated good performance for the epoxidation of cyclooctene and geraniol due to good dispersion and active site isolation. It was easily recycled using a permanent magnet and used three times without loss of catalytic activity and selectivity.
      PubDate: 2017-02-06T03:05:48.710459-05:
      DOI: 10.1002/aoc.3742
       
  • Heteroleptic (N-heterocyclic carbene)–Pd–pyrazole (indazole)
           complexes: Synthesis, characterization and catalytic activities towards
           C–C and C–N cross-coupling reactions
    • Authors: Jin Yang
      Abstract: Eight heteroleptic palladium complexes containing both N-heterocyclic carbenes and NH-heterocycle azoles (pyrazole and indazole) were synthesized and characterized, and their structures were unambiguously confirmed using single-crystal X-ray diffraction. Further investigation of the complexes as catalysts in the Suzuki–Miyaura reaction and Buchwald–Hartwig amination revealed good reactivities for aryl chlorides.Eight heteroleptic (N-heterocyclic carbene)-Pd-(NH-heterocycle azole) complexes were synthesized and used in the Suzuki-Miyaura reaction and Buchwald-Hartwig amination for aryl chlorides.
      PubDate: 2017-02-06T03:01:05.082858-05:
      DOI: 10.1002/aoc.3734
       
  • Silver nanoparticle-decorated multiwalled carbon nanotube/pramipexole
           nanocomposite: Synthesis, characterization and application as an
           antibacterial agent
    • Authors: Ghazaleh Shaham; Hojat Veisi, Malak Hekmati
      Abstract: This work reports the preparation of multiwalled carbon nanotube/pramipexole/Ag (CNT/pra/Ag) as a novel antibacterial agent, in which pramipexole groups are utilized as linkers to secure Ag nanoparticles to carbon nanotube surfaces without agglomeration. The resulting CNT/pra/Ag sample was characterized by performing transmission and scanning electron microscopy, wavelength- and energy-dispersive X-ray, X-ray diffraction, Fourier transform infrared, inductively coupled plasma and Raman measurements. Using this approach, monodisperse spherical Ag nanoparticles in CNT/pra/Ag have narrow size distributions with average diameters of ca 3–8 nm. The antibacterial activity of CNT/pra/Ag was investigated against bacterial species Staphylococcus aureus, methicillin-resistant S. aureus, Pseudomonas aeruginosa and Escherichia coli using the paper-disc diffusion method and by determining the minimal inhibitory concentration. CNT/pra/Ag showed better inhibitory activity towards Gram-positive bacteria than Gram-negative bacteria in this study, which indicates its potential as an antibacterial material for laboratory and medical purposes.Pramipexole was successfully bonded on the surface of MWCNTs with subsequent deposition of Ag NPs to produce a novel antibacterial nanocomposite.
      PubDate: 2017-02-06T03:00:57.718685-05:
      DOI: 10.1002/aoc.3737
       
  • Eco-friendly synthesis of 3,4-dihydroquinoxalin-2-amine,
           diazepine-tetrazole and benzodiazepine-2-carboxamide derivatives with the
           aid of MCM-48/H5PW10V2O40
    • Authors: Esmail Vessally; Rahim Hosseinzadeh-Khanmiri, Ebrahim Ghorbani-Kalhor, Moosa Es'haghi, Ladan Ejlali
      Abstract: A heterogeneous material composed of MCM-48/H5PW10V2O40 was produced and used as an efficient, eco-friendly and highly recyclable catalyst for the one-pot and multicomponent synthesis of 3,4-dihydroquinoxalin-2-amine, diazepine-tetrazole and benzodiazepine-2-carboxamide derivatives in aqueous media and at room temperature with high yields in short reaction times (40–60 min). The recoverable catalyst was easily recycled at least five times without any loss of catalytic activity. The structures of obtained products were confirmed using 1H NMR and 13C NMR spectra.A heterogeneous material, MCM-48/H5PW10V2O40, was produced and used as an efficient, eco-friendly and highly recyclable catalyst for the one-pot multicomponent synthesis of 3,4-dihydroquinoxalin-2-amine, diazepine-tetrazole and benzodiazepine-2-carboxamide derivatives in aqueous media at room temperature with high yields in short reaction times. The recoverable catalyst was easily recycled at least five times without any loss of catalytic activity. The structures of obtained products were confirmed using 1H NMR and 13C NMR spectra.
      PubDate: 2017-02-06T02:57:27.648502-05:
      DOI: 10.1002/aoc.3729
       
  • Syntheses, characterization, antibacterial activity and molecular
           modelling of phenylantimony(III) heteroleptic derivatives containing
           substituted oximes and piperidine dithiocarbamate
    • Authors: Savita Beniwal; Sunil Chhimpa, Deepti Gaur, P.J. John, Yashpal Singh, Jyoti Sharma
      Abstract: Six new heteroleptic phenylantimony(III) derivatives containing substituted oximes and dithiocarbamate moieties of the type (where R = ─C6H5, X = ─CH3 (2a); R = ─C6H4CH3, X = ─CH3 (2b); R = ─C6H4Cl, X = ─CH3 (2c); R = ─C6H4Br, X = ─CH3 (2d); R = ─C6H4OH, X = ─H (2e); R(X)C = (2f)) have been synthesized by the reactions of phenylantimony(III) dichloride with the sodium salt of substituted oximes and dithiocarbamate moiety in unimolar ratio with stirring in dichloromethane. All these newly synthesized derivatives have been characterized using physicochemical and elemental analyses. Structures have been proposed on the basis of infrared, 1H NMR, 13C NMR and LC–MS spectral studies and molecular modelling. In these derivatives the oxime behaves in an unidentate manner whereas dithiocarbamate behaves in a monofunctional anisobidentate manner. Pseudo-trigonal bipyramidal (ψ-TBP) geometry around the antimony metal centre is proposed for these phenylantimony(III) heteroleptic derivatives. The geometry of a representative complex has been optimized through molecular modelling. These newly synthesized derivatives were screened against Bacillus subtilis (Gram-positive) and Escherichia coli (Gram-negative) bacteria to evaluate their antibacterial potential. The structure–activity relationship for antibacterial activity among the four derivatives 2a, 2c, 2e and 2f is discussed.Phenylantimony(III) heteroleptic derivatives containing substituted oxime and dithiocarbamate moiety were synthesized by replacement reactions. Pseudo-trigonal bipyramidal geometry is suggested for these derivatives. The structure–activity relationship among these derivatives is also discussed.
      PubDate: 2017-02-06T02:40:55.104179-05:
      DOI: 10.1002/aoc.3725
       
  • Synthesis of carbamates from carbon dioxide promoted by organostannanes
           and alkoxysilanes
    • Authors: Nicolas Germain; Marko Hermsen, Thomas Schaub, Oliver Trapp
      Abstract: A cooperative methoxy transfer between orthosilicate esters and organotin oxides was developed for the synthesis of various N-alkyl and N-aryl carbamates from carbon dioxide in up to 97% isolated yield. The reaction is highly selective and N-alkylated amines are not observed. Density functional theory calculations of the reaction were performed and, together with NMR observations, a plausible mechanism featuring the catalytic regeneration of dialkyltin dialkoxide is proposed.A synthetic route towards N-alkyl and N-aryl carbamates from carbon dioxide and orthosilicate esters using organotin compounds as catalysts was developed. Isolated yields up to 97% could be achieved and no N-alkylation was observed.
      PubDate: 2017-01-31T03:15:36.461739-05:
      DOI: 10.1002/aoc.3733
       
  • A family of silatrane-armed triazole-encapped salicylaldehyde-derived
           Schiff bases: Synthesis, spectral analysis, and antimicrobial and quantum
           chemical evaluation
    • Authors: Gurjaspreet Singh; Aanchal Arora, Sunita Rani, Pooja Kalra, Darpandeep Aulakh, Mario Wriedt
      Abstract: This work describes the successful synthesis of salicylaldehyde-derived Schiff base-linked organosilicon compounds following a highly efficient click approach. Hydroxyl-terminated Schiff bases were alkylated to bis-acetylenes (1–3) which upon 3 + 2 cycloaddition with 3-azidopropyltriethoxysilane yielded triazole-decorated bis-silanes (4–6). These silanes further underwent base-catalyzed transesterification to afford Schiff base-linked triazole-bound organosilatranes (7–9). The final silatranes as well as precursor alkynes and silanes were comprehensively characterized using NMR (1H and 13C) and infrared spectroscopic techniques together with elemental analysis and mass spectrometry of compounds 7–9. Also, the structures of alkynes 1–3 and silatrane 7 were validated using single-crystal X-ray crystallography. Organosilatranes were initially screened for their pharmacokinetic profile using absorption, distribution, metabolism, excretion and toxicity (ADMET) tools and then explored for their antimicrobial activities, with compound 9 emerging as the most potent antimicrobial agent. Compounds 1–3 and 7–9 also underwent thorough computational analysis by applying the density functional theory (DFT) approach with B3LYP/6-31G(d) level of theory and the results were found to be consistent with the experimental data. Several DFT-based descriptors were also evaluated providing a valuable insight into molecular stability and reactivity.This work describes the synthesis of salicylaldehyde-derived Schiff base-linked organosilicon compounds following a highly efficient click approach. The compounds were well characterized using various spectral techniques and also single-crystal X-ray crystallography. The precursor diynes and final silatranes were also subjected to computational analysis. Organosilatranes were further explored for their photophysical properties and antimicrobial activities with compound 9 emerging as the most potent antimicrobial agent.
      PubDate: 2017-01-31T03:05:47.338659-05:
      DOI: 10.1002/aoc.3728
       
  • Tetrel bonds, penta- and hexa-coordinated tin and lead centres
    • Authors: Sławomir J. Grabowski
      Abstract: A tetrel bond – an interaction between a Group 14 element acting as Lewis acid centre and an electron-donating moiety – is analysed for ZF4 (Z = Sn, Pb) complexes with NH3 and HCN species. MP2/aug-cc-pVTZ calculations were performed and supported by results of the quantum theory of atoms in molecules. The results of calculations show that the tetrel centre may be considered as a pentavalent one if ZF4 interacts with one NH3 or HCN ligand or even as a hexavalent centre if it interacts with two ligands; thus the hypervalency phenomenon is discussed for the complexes analysed here. The theoretical analysis is supported by a discussion of the crystal structures containing the SnF4 fragment; these structures are characterized by a hexa-coordinated tin centre.Tetrel bond – an interaction between a Group 14 element acting as Lewis acid centre and an electron-donating moiety – is analysed for ZF4 (Z = Sn, Pb) complexes with NH3 and HCN species. The Z centre may be considered as pentavalent if ZF4 interacts with one NH3 or HCN ligand or as hexavalent if it interacts with two ligands since all Z─F and Z…N interactions possess covalent character.
      PubDate: 2017-01-31T03:01:09.409554-05:
      DOI: 10.1002/aoc.3727
       
  • Copper(II) Schiff Base Complex Immobilized on Superparamagnetic Fe3O4@SiO2
           as a Magnetically Separable Nanocatalyst for Oxidation of Alkenes and
           Alcohols
    • Authors: Marzieh Sarkheil; Maryam Lashanizadegan
      Abstract: A new heterogeneous catalyst containing a copper(II) Schiff base complex covalently immobilized on the surface of silica-coated Fe3O4 nanoparticles (Fe3O4@SiO2-Schiff base-Cu(II)) was synthesized. Characterization of this catalyst was performed using various techniques. The catalytic potential of the catalyst was investigated for the oxidation of various alkenes (styrene, α-methylstyrene, cyclooctene, cyclohexene and norbornene) and alcohols (benzyl alcohol, 3-methoxybenzyl alcohol, 3-chlorobenzyl alcohol, benzhydrol and n-butanol) using tert-butyl hydroperoxide as oxidant. The catalytic investigations revealed that Fe3O4@SiO2-Schiff base-Cu(II) was especially efficient for the oxidation of norbornene and benzyl alcohol. The results showed that norbornene epoxide and benzoic acid were obtained with 100 and 87% selectivity, respectively. Moreover, simple magnetic recovery from the reaction mixture and reuse for several times with no significant loss in catalytic activity were other advantages of this catalystThe new heterogeneous catalyst (Fe3O4@SiO2-Schiff base-Cu(II)) was synthesis. Characterization of this catalyst was performed by FT-IR, XRD, SEM, TEM, EDS, ICP-OES, CHN, TGA and VSM techniques. This catalyst was especially efficient for oxidation of norbornene and benzyl alcohol. The results of catalyst text showed that norbornene epoxide and benzoic acid were obtained with 100 and 87% selectivity, respectively. Simple magnetic recovery from the reaction mixture and reusability for several times were other advantages of this catalyst.
      PubDate: 2017-01-31T02:50:39.994899-05:
      DOI: 10.1002/aoc.3726
       
  • Preparation of arylmagnesium/lithium from aryl bromides and their coupling
           and substitution reactions in tetrahydrofuran
    • Authors: Ozlem Gundogdu; Ramazan Altundas, Yunus Kara
      Abstract: One-pot synthesis of 2-aryltetrahydrofurans was achieved by a coupling reaction between arylmagnesium bromides prepared in situ and tetrahydrofuran under mild conditions. The reaction between ArBr and n-BuLi gave unexpected butylbenzene derivatives in moderate yields.One-pot synthesis of 2-aryltetrahydrofurans was achieved by a coupling reaction between arylmagnesium bromides prepared in situ and tetrahydrofuran (THF) under mild conditions. The reaction between ArBr and n-BuLi gave unexpected butylbenzene derivatives in moderate yields.
      PubDate: 2017-01-31T02:35:41.657108-05:
      DOI: 10.1002/aoc.3719
       
  • Palladium–cadmium sulfide nanopowder at oil–water interface as an
           effective catalyst for Suzuki–Miyaura reactions
    • Authors: S. Jafar Hoseini; Elham Jahanshahi, Roghayeh Hashemi Fath
      Abstract: A simple and effective strategy is described for the synthesis of Pd–CdS nanopowder by the reduction of an organopalladium(II) complex, [PdCl2(cod)] (cod = cis,cis-1,5-cyclooctadiene), in the presence of CdS quantum dots (QDs) at a toluene–water interface. We investigated the impact of addition of CdS QDs on catalytic activity of Pd nanoparticles (NPs). The Pd–CdS nanopowder functions as an efficient catalyst for Suzuki–Miyaura reactions for the formation of carbon–carbon bonds. There is a high electron density on Pd NPs and due to their high electron affinity they behave as an electron scavenger from CdS increasing the rate of oxidative addition, which is the rate-determining step of the catalytic cycle, and, just as we expect, the C─C coupling reaction with the Pd–CdS nanopowder is faster and occurs in less time than that with Pd nanocatalysts. Compared to classical reactions, this method consistently has the advantages of short reaction times, high yields in a green solvent, reusability of the catalyst without considerable loss of catalytic activity and low cost, and is a facile method for the preparation of the catalyst.A toluene–water planar interface was used as an ideal template for self-assembly of Pd–CdS nanopowder as an efficient catalyst for Suzuki–Miyaura cross-coupling reactions.
      PubDate: 2017-01-31T02:31:16.15118-05:0
      DOI: 10.1002/aoc.3718
       
  • Ferromagnetic nanoparticle-supported copper complex: A highly efficient
           and reusable catalyst for three-component syntheses of 1,4-disubstituted
           1,2,3-triazoles and C–S coupling of aryl halides
    • Authors: Mohammad Mehdi Khodaei; Kiumars Bahrami, Farhat Sadat Meibodi
      Abstract: A new nanocatalyst was synthesized by immobilization of 4′-(4-hydroxyphenyl)-2,2′:6′,2″-terpyridine/CuI complex on ferromagnetic nanoparticles through a surface modification (FMNPs@SiO2-TPy-Cu). This heterogeneous catalyst was characterized using various techniques including Fourier transform infrared and energy-dispersive X-ray spectroscopies, transmission and scanning electron microscopies, X-ray diffraction, vibrating sample magnetometry and thermogravimetric analysis. The resulting nanocatalyst presented excellent catalytic activity for the regioselective syntheses of 1,4-disubstituted 1,2,3-triazoles and thioethers. The thermally and chemically stable, benign and economical catalyst was easily recovered using an external magnet and reused in at least five successive runs without an appreciable loss of activity.Terpyridine/CuI was immobilized on ferromagnetic nanoparticles. This new nanocatalyst was characterized using various techniques and presented excellent catalytic activity for the regioselective syntheses of 1,4-disubstituted 1,2,3-triazoles in H2O–EtOH and thioethers. The benign and economical catalyst was easily recovered and reused in at least five successive runs.
      PubDate: 2017-01-31T01:50:37.147429-05:
      DOI: 10.1002/aoc.3714
       
  • Preparation and characterization of nanomagnetic piperidinium
           benzene-1,3-disulfonate ionic liquid as a novel, green and heterogeneous
           catalyst and its use in the synthesis of
           1H–pyrazolo[1,2-b]phthalazine-5,10-diones and 1H–pyrazolo[1,2-a]
           pyridazine-5,8-diones under solvent-free conditions
    • Authors: Ramin Ghorbani-Vaghei; Jafar Mahmoodi, Yaser Maghbooli
      Abstract: The one-pot four-component synthesis of 1H–pyrazolo[1,2-b]phthalazine-5,10-diones and 1H–pyrazolo[1,2-a]pyridazine-5,8-diones was carried out from the reaction between various aldehydes, malononitrile, hydrazine hydrate and phthalic anhydride or maleic anhydride at 110 °C in solvent-free conditions using piperidinium benzene-1,3-disulfonate nanomagnetic ionic liquid (NMIL) as a novel and reusable catalyst. Some advantages of the presented procedure are a significant reduction in cost, effective catalysis and reusability of the catalyst. NMIL was thoroughly characterized using Fourier transform infrared spectroscopy, X-ray diffraction, scanning and transmission electron microscopies, thermogravimetry, derivative thermogravimetry, Brunauer–Emmett–Teller analysis, vibrating sample magnetometry and energy-dispersive X-ray spectroscopy. The technique is developed as a suitable and safe method for the synthesis of 1H–pyrazolo[1,2-b]phthalazine-5,10-diones and 1H–pyrazolo[1,2-a]pyridazine-5,8-diones making use of an efficient and reusable green catalyst.One-pot four-component synthesis of 1H–pyrazolo[1,2-b]phthalazine-5,10-diones and 1H–pyrazolo[1,2-a]pyridazine-5,8-diones is reported from the reaction of aldehydes, malononitrile, hydrazine hydrate and phthalic anhydride or maleic anhydride under solvent-free conditions using piperidinium benzene-1,3-disulfonate nanomagnetic ionic liquid as a novel and reusable catalyst. Some advantages of the presented procedure are significant reduction in cost, effective catalysis and reusability of the catalyst.
      PubDate: 2017-01-31T01:11:59.431862-05:
      DOI: 10.1002/aoc.3717
       
  • New Rh(III) complexes of 5-methyl-5-(pyridyl)-2,4-imidazolidenedione:
           Synthesis, X-ray structure, electrochemical study and catalytic behaviour
           for hydrogenation of ketones
    • Authors: Seyyed Javad Sabounchei; Mohsen Sayadi, Mojdeh Sadat Hashemi, Ali Hashemi, Davood Nematollahi, Eslam Salahifar, Robert W. Gable
      Abstract: We describe the reaction of anion [RhCl6]3− with a series of hydantoin ligands (HL1, HL2 and HL3 = 5-methyl-5-(2-, 3- and 4-pyridyl)-2,4-imidazolidenedione, respectively). Based on spectroscopic, cyclic voltammetric, elemental and MS analyses, the complexes have the general formula K[RhCl2(L1)2] (1), cis- and trans-K[RhCl4(HL2)2] (2a and 2b) and cis- and trans-K[RhCl4(HL3)2] (3a and 3b). Complexes 2a, 2b, 3a and 3b were characterized successfully using infrared, 1H NMR and 13C NMR spectral analyses. Dissolution of complex 1 in dimethylsulfoxide (DMSO) led to elimination of one KL1 ligand and coordination of two DMSO molecules as ligands and transformation of this complex to cis- and trans-[RhCl2L1(DMSO)2] (1a and 1b). Recrystallization led to separation and isolation of crystals of 1a from the initial mixture. X-ray analysis results showed that this complex was crystallized as solvated complex cis-[RhCl2L1(DMSO)2]DMSO. The catalytic activity of these complexes was then evaluated for the hydrogenation of various ketones.Five new Rh(III) complexes with 5-methyl-5-(pyridyl)-2,4-imidazolidenedione ligands were synthesized and characterized. Single-crystal X-ray diffraction data confirm the octahedral geometry of complex 1a. The Rh(III) complexes 1, 2a, 2b, 3a and 3b were developed as catalysts for hydrogenation of ketones, the catalysts working well at 0.005 mol% loading with conversions up to 95%.
      PubDate: 2017-01-30T03:34:03.555008-05:
      DOI: 10.1002/aoc.3716
       
  • Binding interactions of mixed ligand copper(II) amino acid Schiff base
           complexes with biological targets: Spectroscopic evaluation and molecular
           docking
    • Authors: M. Theetharappan; L. Subha, C. Balakrishnan, M.A. Neelakantan
      Abstract: Three mixed ligand copper(II) complexes [Cu(o-vanillin-l-tryptophan Schiff base)(diimine)] (diimine =2,2′-bipyridine (1), 1,10-phenanthroline (2) and 5,6-dimethyl-1,10-phenanthroline(3)) were synthesized and characterized using analytical and spectral methods. The molecular structures of 1–3 were optimized using density functional theory (DFT) at B3LYP/LanL2DZ levels in the gas phase. Spectral and DFT studies suggest a distorted square pyramidal geometry around the copper ion. Binding interactions of 1–3 with calf thymus DNA and bovine serum albumin protein were studied using UV–visible and fluorescence spectroscopies, viscometric titrations and cyclic voltammetry and also using molecular docking analysis. Studies of the binding of the complexes with calf thymus DNA reveal intercalation, which is supported by molecular docking simulation. The DNA cleavage nature of 1–3 with pUC19 DNA shows that the complexes can cleave DNA without any external agents, and the efficiency follows the order 1 > 3 > 2. Synchronous and three-dimensional fluorescence spectral studies suggest that the secondary structures of the protein are altered by the complexes. Antioxidant studies reveal that the complexes have significant radical scavenging activity against DPPH. In vitro cytotoxic activity of the complexes was evaluated against breast cancer cells (MCF-7), revealing that complex 2 exhibits higher cytotoxicity than the other complexes. Nuclear chromatin condensation and fragmentation were observed with DAPI staining assay. The mitochondrial membrane potential damage was studied by FITC staining assay. Flow cytometric analysis suggests that all the metal complexes induce cell apoptosis.Mixed ligand copper(II) complexes containing a Schiff base and diimine co-ligands were synthesized and characterized. Binding interactions of these complexes with DNA and bovine serum albumin protein were evaluated. DAPI and FITC staining assays were used to study the cytotoxicity.
      PubDate: 2017-01-30T00:26:27.09095-05:0
      DOI: 10.1002/aoc.3713
       
  • Iron oxide nanoparticles coated with green tea extract as a novel
           magnetite reductant and stabilizer sorbent for silver ions: Synthetic
           application of Fe3O4@green tea/Ag nanoparticles as magnetically separable
           and reusable nanocatalyst for reduction of 4-nitrophenol
    • Authors: Hojat Veisi; Fatemeh Ghorbani
      Abstract: Green tea extract having many phenolic hydroxyl and carbonyl functional groups in its molecular framework can be used in the modification of Fe3O4 nanoparticles. Moreover, the feasibility of complexation of polyphenols with silver ions in aqueous solution can improve the surface properties and capacity of the Fe3O4@green tea extract nanoparticles (Fe3O4@GTE NPs) for sorption and reduction of silver ions. Therefore, the novel Fe3O4@GTE NPs nano-sorbent has potential ability as both reducing and stabilizing agent for immobilization of silver nanoparticles to make a novel magnetic silver nanocatalyst (Fe3O4@GTE/Ag NPs). Inductively coupled plasma analysis, transmission and scanning electron microscopies, energy-dispersive X-ray and Fourier transform infrared spectroscopies, and vibrating sample magnetometry were used to characterize the catalyst. Fe3O4@GTE/Ag NPs shows high catalytic activity as a recyclable nanocatalyst for the reduction of 4-nitrophenol at room temperature.Iron oxide nanoparticles coated with green tea extract as a novel magnetite reductant and stabilizer sorbent for silver ions: Synthetic application of Fe3O4@green tea/Ag nanoparticles as magnetically separable and reusable nanocatalyst for reduction of 4-nitrophenol.
      PubDate: 2017-01-30T00:01:28.484475-05:
      DOI: 10.1002/aoc.3711
       
  • In situ synthesis of metallophthalocyanines into pores of MIL-101: A novel
           and green strategy for preparation of host–guest catalysts
    • Authors: Mahmoud Borjian Boroujeni; Alireza Hashemzadeh, Ahmad Shaabani, Mostafa M. Amini
      Abstract: A novel strategy is developed to encapsulate metallophthalocyanines (MPcs, M = Cu, Ni and Co) into MIL-101 to give MPcs@MIL-101 via in situ synthesis of MPcs from component fragments in 1-butyl-3-methylimidazolium bromide as an ionic liquid. This strategy overcomes some drawbacks of existing methods for encapsulation of MPcs into metal–organic frameworks. The chemical and structural properties of MPcs@MIL-101 were determined using scanning electron microscopy, powder X-ray diffraction, and Fourier transformation infrared and flame atomic absorption spectroscopies. The results showed that CuPc@MIL-101, which was used as a ‘ship-in-a-bottle’ catalyst, demonstrates excellent catalytic performance in the oxidative amidation of aldehydes with amine salts. It is confirmed that CuPc@MIL-101 can be reused up to five times without significant loss of its activity.A novel strategy is developed to encapsulate metallophthalocyanines (MPcs) into MIL-101. MPc@MIL-101, which was used as a ‘ship-in-a-bottle’ catalyst, demonstrates excellent catalytic performance in the oxidative amidation of aldehydes with amine salts.
      PubDate: 2017-01-24T01:50:45.194498-05:
      DOI: 10.1002/aoc.3715
       
  • Review: Quantitative structure–activity/property relationships as
           related to organotin chemistry
    • Authors: George Eng
      Abstract: The aim of this review is to examine the current status of quantitative structure–activity/property relationships (QSAR/QSPR) as related to organotin chemistry. QSAR/QSPR are mathematical models that relate some measurable biological activity or physical property in a series of similar compounds to a descriptor or descriptors associated with the molecules. Descriptors used in QSAR/QSPR studies are endless, from traditional parameters to newly developed ones. They range from quantum chemical descriptors to physicochemical parameters while QSAR/QSPR studies range from predicting bio-toxicity of various species to estimating chromatographic parameters. The intent of the review is to provide investigators with the current state of knowledge and trends in this area.A review of quantitative structure–activity/property relationships as pertaining to organotin chemistry is presented. The current state of knowledge and trends are examined.
      PubDate: 2017-01-24T01:45:44.019253-05:
      DOI: 10.1002/aoc.3712
       
 
 
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