JournalTOCs

Applied Organometallic Chemistry
[SJR: 0.632] [H-I: 58] [7 followers] Follow

Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0268-2605 - ISSN (Online) 1099-0739
Published by John Wiley and Sons

[1577 journals]

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
Facile synthesis of PtSnZn nanosheet thin film at oil–water interface by
use of organometallic complexes: An efficient catalyst for methanol
oxidation and p-nitrophenol reduction reactions
- Authors: Sajad Saberi Sarmoor; S. Jafar Hoseini, Roghayeh Hashemi Fath, Mahmoud Roushani, Mehrangiz Bahrami
  Abstract: PtSnZn nanosheet thin film with stable and high activity towards methanol electro-oxidation was synthesized via a simple reduction of organometallic precursors including [PtCl2(cod)] (cod = cis,cis-1,5-cyclooctadiene) and [Sn(CH3)4] complexes, in the presence of [Zn(acac)2] (acac = acetylacetonate) complex at toluene–water interface. Catalytic activities of PtSnZn nanosheets were investigated in the p-nitrophenol (p-Nip) reduction and methanol oxidation reactions. The obtained results demonstrate that PtSnZn nanosheets exhibit a good electrocatalytic performance for methanol oxidation reaction, the catalytic activity of the PtSnZn nanosheets being at least 3.5 times higher than that of Pt nanoparticle thin film. Also, the apparent rate constant obtained for p-Nip reduction with the PtSnZn nanosheets is at least 2.3 times higher than that for Pt nanoparticle thin film due to the appropriate interaction between platinum, tin and zinc metals and geometric properties of PtSnZn nanosheet thin film. Nanosheets are highly favourable for superior catalytic performances due to their geometric properties. A facile and efficient route was used to synthesize trimetallic alloy thin film at oil–water interface.A planar toluene–water interface was used as an ideal template for self-assembly of PtSnZn nanosheet thin film. The PtSnZn nanosheets are an efficient catalyst for methanol oxidation and p-nitrophenol reduction reactions.
  PubDate: 2017-08-15T02:55:38.254095-05:
  DOI: 10.1002/aoc.3979
Synthesis, characterization and photocatalytic application of
TiO2/magnetic graphene for efficient photodegradation of crystal violet
- Authors: Zahra Aalimohammadi Piranshahi; Mohammad Behbahani, Fatemeh Zeraatpisheh
  Abstract: A magnetized nano-photocatalyst based on TiO2/magnetic graphene was developed for efficient photodegradation of crystal violet (CV). Scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy and elemental mapping were used to characterize the prepared magnetic nano-photocatalyst. The photocatalytic activity of the synthesized magnetic nano-photocatalyst was evaluated using the decomposition of CV as a model organic pollutant under UV light irradiation. The obtained results showed that TiO2/magnetic graphene exhibited much higher photocatalytic performance than bare TiO2. Incorporation of graphene enhanced the activity of the prepared magnetic nano-photocatalyst. TiO2/magnetic graphene can be easily separated from an aqueous solution by applying an external magnetic field. Effects of pH, magnetized nano-photocatalyst dosage, UV light irradiation time, H2O2 amount and initial concentration of dye on the photodegradation efficiency were evaluated and optimized. Efficient photodegradation (>98%) of the selected dye under optimized conditions using the synthesized nano-photocatalyst under UV light irradiation was achieved in 25 min. The prepared magnetic nano-photocatalyst can be used in a wide pH range (4–10) for degradation of CV. The effects of scavengers, namely methanol (OH• scavenger), p-benzoquinone (O2•− scavenger) and disodium ethylenediaminetetraacetate (hole scavenger), on CV photodegradation were investigated.A synthesized magnetic nano-photocatalyst showed strong synergetic effect between graphene nanosheets and TiO2, which improved charge separation properties. The photocatalytic ability of the synthesized magnetic nano-photocatalyst was evaluated using degradation of crystal violet (CV) as a model organic pollutant under UV light irradiation. The efficiency of degradation of CV in the presence and absence of hydrogen peroxide was >98% after 60 and 25 min, respectively.
  PubDate: 2017-08-15T02:50:55.979628-05:
  DOI: 10.1002/aoc.3985
Dimethyltin(IV) complexes derived from hydroxamic acid and acylhydrazone
- Authors: Kai Liu; Guoliang Chang, Hui Yan, Zhen Li, Min Hong, Meiju Niu
  Abstract: Two novel dimethyltin(IV) complexes, Me2SnL1(PyCOO)(MeOH) (1) and Me2SnL2 (2) (HL1 = 4-pyridinehydroxamic acid and H2L2 = 2-hydroxy-N′-[(2-hydroxy-5-chlorophenyl)methylidene]benzoylhydrazone), were synthesized and characterized using elemental analyses, Fourier transform infrared and NMR (1H, 13C) spectroscopies and single-crystal X-ray diffraction. In complex 1 the geometry around the tin atom is a six-coordinated distorted octahedral configuration, while complex 2 exhibits five-coordinated distorted trigonal bipyramid geometry. Preliminary in vitro cytotoxicity studies with two human cancer cell lines (HeLa and A549) using MTT assay show that complex 1 is more potent than complex 2. The interactions of the two complexes with calf thymus DNA and bovine serum albumin were also investigated using UV–visible absorption spectral, thermal denaturation and viscosity measurements and docking analysis. Investigations indicate that the structures of the mixed ligands play an important role in the properties of the dimethyltin(IV) complexes, and, to some extent, the antitumor activities of the complexes are partly related to interactions with DNA and some proteins in cancer cells.Two dimethyltin(IV) complexes were synthesized and characterized using some spectroscopy methods and single-crystal X-ray diffraction. In vitro cytotoxicity studies with two human cancer cell lines using MTT assay show that complex 1 is more potent than complex 2 and cisplatin. The results of the interaction of the complexes with CT-DNA and BSA indicated that the mixed ligands play an important role in the properties of the complexes. These studies could be helpful in the development of organotin complexes potential pharmaceutical application.
  PubDate: 2017-08-15T02:45:47.849464-05:
  DOI: 10.1002/aoc.3973
Metal complexes of chalcone analogue: Synthesis, characterization, DNA
binding, molecular docking and antimicrobial evaluation
- Authors: Faten M. Atlam; Marwa N. El-Nahass, Eman A. Bakr, Tarek A. Fayed
  Abstract: A novel chalcone, namely 5-(4-(dimethylamino)phenyl)-1-(thiophen-2-yl)penta-2,4-dien-1-one, DMATP, and its complexes with nickel(II), vanadium(III), palladium(II) and platinum(II) metal ions were synthesized and characterized using a set of chemical and spectroscopic tools including elemental analysis, electrical conductance, magnetic susceptibility and spectral techniques. The interactions of the synthesized chalcone and its metal complexes with DNA were studied using steady-state absorption and emission techniques as well as viscosity and electrochemical measurements. The obtained results confirm DNA intercalation. Additionally, theoretical studies were performed for all the investigated compounds using DFT/B3LYP calculations. The optimized geometries are found to be in good agreement with the suggested experimental structures. The bond lengths, bond angles, chemical reactivity, energy components, binding energy and dipole moment were evaluated. Also, theoretical infrared intensities and thermodynamic parameters for all compounds were calculated. Molecular docking calculations show that the Ni(II) complex exhibits the highest DNA binding activity, which agrees well with the experimental results. Finally, the compounds were screened for antimicrobial activity using several microorganisms.
  PubDate: 2017-08-11T04:42:33.180821-05:
  DOI: 10.1002/aoc.3951
Synthesis, characterization and application of alumina/ vanadium pentoxide
nanocomposit by sol–gel method
- Authors: Hassan Hassani; Batol Zakerinasab, Hoda Hossien Poor
  Abstract: In this work, we report the preparation of Al2O3/V2O5 nanocomposit using vanadium and aluminum nitrate by sol–gel method. Characterization of nanocomposit was carried out by powder X-ray diffractometry (XRD), Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), Energy-Dispersive X-ray (EDX) and UV spectroscopy. Then, applicability of the synthesized nanocomposit was tested as a nanocatalyst for the synthesis of diindolyl oxindole derivatives, an important class of potentially bioactive compounds. The products were obtained in good to high yields from one-pot three-component condensation of isatin with indole. Also, this nanocatalyst has been reused several times, without observable loss of activity.In this work, we report the preparation of Al2O3/V2O5 nanocomposit by sol–gel method. Also, Al2O3/ V2O5 nanocomposit was used for the synthesis of diindolyl oxindole derivatives in good to high yields.
  PubDate: 2017-08-11T04:41:06.059051-05:
  DOI: 10.1002/aoc.3945
Facile Chemoselective synthesis of
2-(2-(Methoxycarbonyl)-3-oxo-2,3-dihydrobenzofuran-2-yl)benzoic acids and
3H,3’H-Spiro[benzofuran-2,1′-isobenzofuran]-3,3′-dione derivatives
- Authors: Neda Firoozi; Zohreh Roshan, Mohammad Reza Mohammadizadeh
  Abstract: Oxidation of some derivatives of 4b,9b–dihydroxyindeno[1,2-b]benzofuran-10-one have been investigated in detail using lead(IV) acetate in acetic acid under reflux conditions and periodic acid in aqueous ethanol at room temperature. We realized that during the first 5–15 minutes of the oxidation reactions in lead(IV) acetate/acetic acid system, 3H,3’H-spiro[benzofuran-2,1′-isobenzofuran]-3,3′-dione derivatives have been synthesized chemo selectively, while, if the reaction mixtures stirred for additional 3 hours, the main products would be 2-(2-(Methoxycarbonyl)-3-oxo-2,3-dihydrobenzofuran-2-yl)benzoic acids. Moreover, room temperature oxidation of 4b,9b–dihydroxyindeno[1,2-b]benzofuran-10-ones by periodic acid (H5IO6), leads to the formation of 3H,3’H-spiro[benzofuran-2,1′-isobenzofuran]-3,3′-dione derivatives in good to excellent yields.3H,3'H-Spiro[benzofuran-2,1'-isobenzofuran]-3,3'-diones were chemoselectively obtained as the major products during first 15 minutes of the oxidation reactions of 4b,9b-dihydroxyindeno[1,2-b]benzofuran-10-ones with lead(IV) acetate in acetic acid. Interestingly, if the oxidation reactions were continued for 3 hours, 2-(2-(methoxycarbonyl)-3-oxo-2,3-dihydrobenzofuran-2-yl)benzoic acid derivatives would be obtained in moderate to good yields. Additionally, oxidation of dihydroxyindeno[1,2-b]benzofuran-10-ones with periodic acid in aqueous media resulted in the formation of 3H,3'H-spiro[benzofuran-2,1'-isobenzofuran]-3,3'-diones.
  PubDate: 2017-08-11T04:36:42.911124-05:
  DOI: 10.1002/aoc.3963
Syntheses, silylation, characterization, and antimicrobial and
antifertility activities of organoboron derivatives of some bioactive
monofunctional bidentate semicarbazones
- Authors: Jyoti Bhomia; Jyoti Sharma, Rucha Lakhne, Rachna Sharma, R.S. Gupta, Ram Avatar Sharma, Yashpal Singh
  Abstract: Some new mononuclear organoboron derivatives of the type PhBL1–5(OH) (1a–1e) were synthesized by the reaction of PhB(OH)2 and LH (LH = OC(NH2)NH:NC(CH3)4C6H4R, where R = H (L1H); CH3(L2H); OCH3(L3H); Cl (L4H); Br (L5H)) in 1:1 molar ratio in refluxing tetrahydrofuran (THF). This was followed by the reactions of PhBL1–5(OH) with NH(SiMe3)2 in 2:1 molar ratio in THF to yield new heterodinuclear derivatives of the type PhBL1–5(OSiMe3) (2a–2e). All these newly synthesized complexes were characterized using elemental analyses and their probable structure was proposed on the basis of infrared, 1H NMR, 13C NMR, 11B NMR and 29Si NMR spectral data and mass spectrometry. Semicarbazone ligands and their corresponding mono- and heterodinuclear boron derivatives were screened against pathogenic bacteria (E. coli and P. aeruginosa) and fungi (A. niger and P. peniculosum) to examine their antimicrobial activities. Representative compounds of each series of mono- and heterodinuclear boron derivatives and a ligand were screened for their antifertility activity on male adult Wistar rats.Antimicrobial and antifertility activities of semicarbazones and their corresponding mono- and heterodinuclear boron derivatives have been investigated with a view to examining their potential as drugs.
  PubDate: 2017-08-11T04:36:06.328177-05:
  DOI: 10.1002/aoc.3983
Ni(II)-Adenine complex coated Fe3O4 nanoparticles as high reusable
nanocatalyst for the synthesis of polyhydroquinoline derivatives and
oxidation reactions
- Authors: Taiebeh Tamoradi; Mohammad Ghadermazi, Arash Ghorbani-Choghamarani
  Abstract: In the present study, Fe3O4 nanoparticles were prepared via simple and versatile procedure. Then, a novel and green catalyst was synthesized by the immobilization of Ni on Fe3O4 nanoparticles coated with adenine. The activity of this nanostructure compound was examined for the oxidation of sulfides, oxidative coupling of thiols and synthesis of polyhydroquinolines. The prepared catalyst was characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), inductively coupled plasma optical emission spectroscopy (ICP-OES), X-ray Diffraction (XRD), thermal gravimetric analysis (TGA), and vibrating sample magnetometer (VSM) measurements. This organometallic catalyst was recovered by the assistance of an external magnetic field from the reaction mixture and reused for seven continuous cycles without noticeable change in its catalytic activity.Ni(II)-Adenine complex coated Fe3O4 nanoparticles has been prepared and characterized with different techniques. This nano structural compound applied as an efficient catalyst for the oxidation of sulfides, oxidative coupling of thiols and synthesis of polyhydroquinolines.
  PubDate: 2017-08-08T05:31:05.285717-05:
  DOI: 10.1002/aoc.3974
Uniformly dispersed copper nanoparticles onto the modified magnetically
recoverable nanocatalyst for aqueous synthesis of primary amides
- Authors: Fariborz Ziaee; Mostafa Gholizadeh, Seyed Mohammad Seyedi
  Abstract: Magnetically recoverable and environmentally friendly Cu-based heterogeneous catalyst has been synthesized for the one-pot conversion of aldehydes to their corresponding primary amides. The Fe3O4@SiO2 nanocomposites were prepared by synthesis of Fe3O4 magnetic nanoparticles (MNPs) which was then coated with a silica shell via Stöber method. Bi-functional cysteine amino acid was covalently bonded onto the siliceous shell of nanocatalyst. The CuII ions were then loaded onto the modified surface of nanocatalyst. Finally, uniformly dispersed copper nanoparticles were achieved by reduction of CuII ions with NaBH4. Amidation reaction of aryl halides with electron-withdrawing or electron-donating groups and hydroxylamine hydrochloride catalyzed with Fe3O4@SiO2@Cysteine-copper (FSC-Cu) MNPs in aqueous condition gave an excellent yield of products. The FSC-Cu MNPs could be easily isolated from the reaction mixture with an external magnet and reused at least 8 times without significant loss in activity.Magnetically recoverable and environmentally friendly Cu-based heterogeneous catalyst has been synthesized for the one-pot conversion of aldehydes to their corresponding primary amides. Cysteine was used as a ligand for modification of silica coated magnetic nanoparticles which used for generation of Cu NPs. The mild reaction conditions, broad substrate scope make FSC-Cu MNPs efficient and environmentally friendly for the synthesis of primary amides.
  PubDate: 2017-08-01T23:12:24.996548-05:
  DOI: 10.1002/aoc.3925
Reaction of dimethylplatinum(II) complexes with PhCH2CH2Br: Comparative
reactivity with CH3CH2Br and PhCH2Br and synthesis of Pt(IV) complexes
- Authors: Mozhgan Samandar Sangari; Mehdi Rashidi, S. Masoud Nabavizadeh, Banafshe Askari, Fatemeh Niroomand Hosseini
  Abstract: Oxidative addition of 2-phenylethylbromide (PhCH2CH2Br) to dimethylplatinum(II) complexes [PtMe2(NN)] (1a, NN = 2,2′-bipyridine (bpy); 1b, NN = 1,10-phenanthroline (phen)) afforded the new organoplatinum(IV) complexes [PtMe2(Br)(PhCH2CH2)(bpy)], as a mixture of trans (2a) and cis (3a) isomers, and [PtMe2(Br)(PhCH2CH2)(phen)], as a mixture of trans (2b) and cis (3b) isomers, respectively. The new Pt(IV) complexes were readily characterized using multinuclear (1H and 13C) NMR spectroscopy and elemental microanalysis. The crystal structure of 2a was further determined using X-ray crystallography indicating an octahedral geometry around the platinum centre. A comparison of reactivity of RCH2Br reagents (R = CH3, Ph or PhCH2) in their oxidative addition reactions with complex 1a, with an emphasis on the effects of the R groups of alkyl halides, was also conducted using density functional theory.Oxidative addition of 2-phenylethylbromide to dimethylplatinum(II) complexes afforded new organoplatinum(IV) complexes as a mixture of trans and cis addition products.
  PubDate: 2017-07-28T06:28:56.77112-05:0
  DOI: 10.1002/aoc.3954
A ferrocene-containing porous organic polymer linked by tetrahedral
silicon-centered units for gas sorption
- Authors: Qingyu Ma; Yipeng Qi, Jianquan Li, Weiguo Wang, Xuejiao Sun
  Abstract: A novel ferrocene-containing porous organic polymer (FPOP) has been prepared by Sonogashira-Hagihara coupling reaction of 1,1′-dibromoferrocene and tetrakis(4-ethynylphenyl)silane. Compared with other polymers, the resulting polymer possesses excellent thermal stability with the decomposition temperature of 415°C and high porosity with Brunauer–Emmett–Teller (BET) surface area of 542 m2 g−1 as measured by nitrogen adsorption-desoprtion isotherm at 77 K. For applications, it shows moderate carbon dioxide uptakes of up to 1.42 mmol g−1 (6.26 wt%) at 273 K/1.0 bar and 0.82 mmol g−1 (3.62 wt%) at 298 K/1.0 bar, and hydrogen capacity of up to 0.45 mmol g−1 (0.91 wt%) at 77 K/1.0 bar, indicating that FPOP might be utilized as a promising candidate for storing carbon dioxide and hydrogen. Although FPOP possesses lower porosity than many porous polymers, the gas capacities are higher or comparable to them, thereby revealing that the incorporation of ferrocene units into the network is an effective strategy to enhance the affinity between the framework and gas.A novel ferrocene-containing porous organic polymer (FPOP) constructed from 1,1′-dibromoferrocene and tetrakis(4-ethynylphenyl)silane exhibits excellent thermal stability, high porosity and can be utilized as a promising candidate for storing CO2 and H2.
  PubDate: 2017-07-27T01:56:27.836705-05:
  DOI: 10.1002/aoc.3935
2-Arylation/alkylation of benzothiazoles using superparamagneticgraphene
oxide-Fe3O4 hybrid material as a heterogeneous catalystwith diisopropyl
azodicarboxylate (DIAD) as an oxidant
- Authors: Dariush Khalili; Elham Etemadi-Davan, Ali Reza Banazadeh
  Abstract: In this report, we introduced Graphene oxide-iron oxide (GO-Fe3O4) nanocomposites as a heterogeneous catalyst for arylation/alkylation of benzothiazoles with aldehydes and benzylic alcohols in the presence of diisopropyl azodicarboxylate (DIAD) as an oxidant which exclusively produced 2-aryl (alkyl)-1H–benzothizoles in moderate to excellent yields. The absence of precious metals and toxic solvent, easy product isolation, and recyclability of the GO-Fe3O4 with no loss of activity are notable advantages of this method.We introduced Graphene oxide-iron oxide (GO-Fe3O4) nanocomposites as a heterogeneous catalyst for arylation/alkylation of benzothiazoles with aldehydes and benzylic alcohols in the presence of diisopropyl azodicarboxylate (DIAD) as an oxidant which exclusively produced 2-aryl (alkyl)-1H–benzothizoles in moderate to excellent yields.
  PubDate: 2017-07-27T01:55:48.269882-05:
  DOI: 10.1002/aoc.3971
Cross-coupling reactions using porous multipod Cu2O microcrystals as
recoverable catalyst in aqueous media
- Authors: Lin Tang; Chaoting Wu, Qiyan Hu, Qian Li, Wu Zhang
  Abstract: Porous multipod Cu2O microcrystals were found to be an efficient, highly recyclable and eco-friendly catalyst for the cross-coupling reactions of aryl halides and terminal alkynes with high yields in aqueous media. Noteworthy, the Cu2O catalyst can be reused for several times without significant decrease in catalytic activity.Porous multipod Cu2O microcrystals were found to be an efficient, highly recyclable and eco-friendly catalyst for the cross-coupling reactions of aryl halides and terminal alkynes with high yields in aqueous media.
  PubDate: 2017-07-27T01:50:45.257401-05:
  DOI: 10.1002/aoc.3980
CuO nanoparticles supported on three-dimensional nitrogen-doped graphene
- Authors: Seyed Ghorban Hosseini; Zahra Khodadadipoor, Mojtaba Mahyari
  Abstract: In the present work, CuO nanoparticles grown on three-dimensional nitrogen-doped graphene-based frameworks (CuO@3D-(N)GFs) were synthesized using a two-step method. After the synthesis of three-dimensional nitrogen-doped graphene, CuO nanoparticles were deposited on it, by adding cupric acetate followed by thermal treatment. Different analysis methods were used to characterize the products. The as-prepared nanocomposite was used as a promising catalyst for thermal decomposition of ammonium perchlorate (AP) as one of the most common oxidizer in composite propellants. Differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA) techniques were used to investigate the thermal decomposition of ammonium perchlorate. According to the DSC/TGA, high temperature decomposition of AP decreased to 111 °C in the presence of 4% CuO@3D-(N)GFs and the total heat release (ΔH) from decomposition of AP increased to 1893 J g−1 which is much more than 590 J g−1 for pure AP.CuO nanoparticles grown on three-dimensional nitrogen-doped graphene based-frameworks (CuONPs@3D-(N)GFs) were found to be an efficient stable catalyst for the thermal decomposition of ammonium perchlorate.
  PubDate: 2017-07-27T01:45:50.43001-05:0
  DOI: 10.1002/aoc.3959
Graphene-mesoporous anatase TiO2 nanocomposite: A highly efficient and
recyclable heterogeneous catalyst for one-pot multicomponent synthesis of
benzodiazepine derivatives
- Authors: Mohd Shoeb; Mohammad Mobin, Abad Ali, Shamsuz Zaman, Alim H. Naqvi
  Abstract: The potential to bias chemical reaction pathways is a significant goal for physicists and material researchers to design revolutionary materials. Recently, two-dimensional materials have appeared as a promising candidate for exploring novel catalyst activity in organic reaction. In this context, herein we report an easy and efficient synthesis of substituted benzodiazepines in high yields through the graphene-based mesoporous TiO2 nanocomposite (Gr@TiO2 NCs) catalyst. To validate the merits of the Gr@TiO2 NCs as a catalyst, we have also designed TiO2 nanoparticle (NPs) under similar conditions. Successful comprehension realization of Gr@TiO2 NCs and TiO2 NPs were concluded from the XRD, SEM, HR-TEM, EDS elemental mapping, FT-IR, Raman, UV–Vis and TGA analysis. Gr@TiO2 NCs has the propitious catalyst performance (~98%) over the TiO2 NPs (~77%), which could be scrutinized in terms of graphene support toward the TiO2 NPs and enable the large contact area between graphene and TiO2 NPs. Incorporated graphene maintaining TiO2 as a catalytically active and attracting electron to site isolation, as well as protecting TiO2 from oxidative degradation during the reaction. Moreover, the role of graphene is suggested to prolonged reaction duration, yield and unaltered throughout the reaction because of the π-π interaction between graphene and TiO2 NPs. Additionally, the catalyst is recycled by filtration and reprocessed six times without having a significant loss in its catalytic activity.We have successfully synthesized graphene bonded and mesoporous anatase TiO2 NPs through an ex-situ hybridization strategy. Gr@TiO2 NCs play a role in the reaction mechanism for coupling of o-phenylenediamine, dimedone, and aldehydes so as to synthesize benzodiazepine derivatives.
  PubDate: 2017-07-27T01:40:51.832524-05:
  DOI: 10.1002/aoc.3961
Synthesis of graphene oxide supported copper–cobalt ferrite material
functionalized by arginine amino acid as a new high–performance catalyst
- Authors: Rahim Ghadari; Hassan Namazi, Mohammad Aghazadeh
  Abstract: A novel Cu0.5Co0.5Fe2O4@Arg–GO catalytic system was successfully prepared by immobilization of copper substituted cobalt ferrite nanoparticles on arginine–grafted graphene oxide nanosheets, in which ferrite moiety acts as an oxidation catalyst and arginine has the role of base catalyst. Also, arginine amino acid was used to modify the surface of graphene oxide nanosheets which the prepared support can improve dispersion and uniform loading of nanoparticles. The prepared nanocomposite was characterized by flame atomic absorption spectroscopy (FAAS), inductively coupled plasma optical emission spectrometer (ICP–OES), energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FT–IR), ultraviolet–visible spectroscopy (UV–vis), Raman spectroscopy, thermogravimetric analysis (TGA), x–ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) analysis. The prepared Cu0.5Co0.5Fe2O4@Arg–GO nanocomposite was used as an efficient catalyst for one–pot tandem oxidative synthesis of 2–phenylbenzimidazole derivatives in good yields.Arginine amino acid was attached to the surface of graphene oxide nanosheets to produce a green support for immobilization of copper substituted cobalt ferrite nanoparticles. The prepared catalyst was used for the one-pot tandem oxidative cyclization of primary alcohols with o-phenylenediamines to produce benzimidazoles under aerobic oxidation conditions, with efficient activity and reusability.
  PubDate: 2017-07-27T01:35:51.360482-05:
  DOI: 10.1002/aoc.3965
Green route for selective gram-scale oxidation of sulfides using
tungstate/triazine-based ionic liquid immobilized on magnetic
nanoparticles as a phase-transfer heterogeneous catalyst
- Authors: Seyed Hassan Hosseini; Maryam Tavakolizadeh, Nasrin Zohreh, Rouhollah Soleyman
  Abstract: Tungstate ions were successfully loaded onto triazine-based ionic liquid-functionalized magnetic nanoparticles through an anion exchange process. The use of triazine core for creating ionic liquid led to the immobilization of high amounts of WO42−. The resulting catalyst showed high activity and selectivity in the oxidation of sulfides to sulfoxides with H2O2 as a green oxidant at room temperature. In addition, due to the presence of ammonium groups in the catalyst structure, water dispersibility of the catalyst was increased. More important, the catalyst was magnetically recovered and reused for up to six runs without any marked decrease of activity and selectivity. Finally, easy gram-scale oxidation of methylphenyl sulfide as well as fast separation of catalyst and product makes the protocol economical and industrially applicable.Simple preparation of tungstate/triazine-based ionic liquid immobilized on magnetic nanoparticles is provided as a phase-transfer catalyst for gram-scale selective oxidation of sulfides using 0.4 mol% catalyst loading. H2O and H2O2 used as green solvent and oxidant. Reusability of catalyst is up to 6 subsequent runs without significant loss of activity or leaching.
  PubDate: 2017-07-27T01:31:35.686901-05:
  DOI: 10.1002/aoc.3953
Molecular structure, molecular docking, thermal, spectroscopic and
biological activity studies of bis-Schiff base ligand and its metal
complexes
- Authors: Ehab M. Zayed; Ahmed M.M. Hindy, Gehad G. Mohamed
  Abstract: Coordination compounds of Fe(III), Zn(II), Ni(II), Co(II), Cu(II), Cd(II) and Mn(II) ions were synthesized from the ligand [4,4′-((((ethane-1,2-diylbis(oxy))bis(2,1-phenylene))bis(methanylylidene))bis(azanylylidene))diphenol]ethane (H2L) derived from the condensation of bisaldehyde and 4-aminophenol. Microanalysis, magnetic susceptibility, infrared, 1H NMR and mass spectroscopies, molar conductance, X ray powder diffraction and thermal analysis were used to confirm the structure of the synthesized chelates. According to the data obtained, the composition of the 1:1 metal ion–bis-Schiff base ligand was found to be [M(H2L)(H2O)2]Cln (M = Zn(II), Ni(II), Co(II), Cu(II), Cd(II) and Mn(II), n = 2; Fe(III), n = 3). Magnetic susceptibility measurements and reflectance spectra suggested an octahedral geometry for the complexes. Central metals ions and bis-Schiff base coordinated together via O2 and N2 donor sites which as evident from infrared spectra. The Gaussian09 program was applied to optimize the structural formula for the investigated Schiff base ligand. The energy gaps and other important theoretical parameters were calculated applying the DFT/B3LYP method. Molecular docking using AutoDock tools was utilized to explain the experimental behaviour of the Schiff base ligand towards proteins of Bacillus subtilis (5 h67), Escherichia coli (3 t88), Proteus vulgaris (5i39) and Staphylococcus aureus (3ty7) microorganisms through theoretical calculations. The docked protein receptors were investigated and the energies of hydrogen bonding were calculated. These complexes were then subjected to in vitro antibacterial studies against several organisms, both Gram negative (P. vulgaris and E. coli) and Gram positive (S. pyogones and B. subtilis). The ligand and metal complexes exhibited good microbial activity against the Gram-positive and Gram-negative bacteria.Optimized structure, and HOMO and LUMO patterns of bis-Schiff base ligand.
  PubDate: 2017-07-27T01:31:19.896239-05:
  DOI: 10.1002/aoc.3952
Hydrogenation of nitroarenes catalyzed by a dipalladium complex
- Authors: Ming-Uei Hung; Shu-Ting Yang, Mani Ramanathan, Shiuh-Tzung Liu
  Abstract: A dipalladium complex [Pd2(L)Cl2](PF6)2 (2), via the substitution of (PhCN)2PdCl2 with 5-phenyl-2,8-bis(6′-bipyridinyl)-1,9,10-anthyridine (L) followed by the anion exchange, was found to be a good pre-catalyst for the reduction of nitroarenes to yield the corresponding anilines under atmospheric pressure of hydrogen in methanol. This method provides a straightforward access to a diverse array of functionalized anilines, exhibiting a possible application in synthetic chemistry. The catalytic activity of this complex is enhanced by the di-metallic system via the synergistic effect.A dipalladium complex resulting from complexation of [Pd(CH3CN)2Cl2] with 5-phenyl-2,8-bis(6′-bipyridinyl)-1,9,10-anthyridine has found to be a good catalyst for reduction of nitroarenes into the corresponding anilines under atmospheric pressure of hydrogen, presumably due to the cooperative interaction between metal ions.
  PubDate: 2017-07-27T01:26:13.296188-05:
  DOI: 10.1002/aoc.3976
Fe3O4@S-ABENZ@VO: Magnetically separable nanocatalyst for the efficient,
- Authors: Somaieh Rezaei; Arash Ghorbani-Choghamarani, Rashid Badri, Ahmad Nikseresht
  Abstract: Oxovanadium(IV) immobilized on Fe3O4@S-ABEN is reported as a highly efficient nanocatalyst for the oxidation of sulfides and oxidative coupling of thiols (using H2O2 as green oxidant), the products of which are obtained in high to excellent yields. The products can be separated by a simple extraction with organic solvent and the catalyst is highly efficient, especially in terms of selectivity of desired product. The catalytic system can be recycled and reused without significant loss of catalytic activity.Fe3O4@S-ABEN has been prepared as new nanocatalyst and characterized by different techniques. This nano structural compound applied for the oxidation of sulfides and oxidative coupling of thiols using H2O2, as green oxidant.
  PubDate: 2017-07-27T01:22:01.637843-05:
  DOI: 10.1002/aoc.3948
Copper(I) complex covalently anchored on graphene oxide as an efficient
and recyclable catalyst for Sonogashira reaction
- Authors: Roghayeh Hashemi Fath; S. Jafar Hoseini
  Abstract: In this study, the organosilane-functionalized graphene oxide as a stabilizer was prepared by a facile one-step silylation approach. [Cu(PPh3)3Cl] complex was successfully immobilized onto the graphene oxide surface through coordination interaction with organosilane ligand spacers. The supported catalyst showed enhanced catalytic performance toward Sonogashira reaction of aryl halides with phenylacetylene in water solvent compared with the homogeneous analogues, and it could be readily recycled and reused several times without discernible loss of its activity.Copper(I) complex was covalently anchored onto the graphene oxide surface through coordination interaction by employing (3-aminopropyl)triethoxysilane ligand spacers and were used as efficient catalyst in the Sonogashira reaction.
  PubDate: 2017-07-21T06:01:09.871242-05:
  DOI: 10.1002/aoc.3964
A comparative study on the catalytic performance of heme and non-heme
catalysts: Metal porphyrins versus metal Schiff bases
- Authors: Atefeh Talaeizadeh; Mahdi Tofighi, Saeed Zakavi
  Abstract: Catalytic activity and oxidative stability of a series of iron and manganese porphyrins with 2-chlorophenyl, phenyl and 4-methoxyphenyl at the meso positions and metallosalens (Mn- and Fe-salens) including N,N′-bis(salicylidene)ethylenediamine, N,N′-bis(5- chlorosalicylidene)ethylenediamine and N,N′-bis(2,4-dihydroxysalicylidene)ethylenediamine for the oxidation of olefins with tetra-n-butylammonium periodate (TBAP) and tetra-n-butyl-ammonium Oxone (TBAO) have been investigated and compared. Although the metalloporphyrins showed an increased catalytic activity relative to the Schiff base complexes, the former provided no significant catalytic advantage over the latter. Also, a comparable or slightly higher oxidative stability was observed for the Schiff base complexes under the reaction conditions. Furthermore, in spite of large difference between the oxidizing ability of TBAO and TBAP, similar patterns were observed for the order of catalytic activity and oxidative stability of the used heme and non-heme catalysts. The introduction of a methyl group at the ɑ position of styrene led to an increase in its reactivity, indicating the dominance of electronic effects over the steric ones in these catalytic systems.The oxidation of olefins with tetra-butylammonium periodate and Oxone was conducted in the presence of the manganese and iron complexes of a series of porphyrins and Schiff bases to compare their relative catalytic activity and oxidative stability.
  PubDate: 2017-07-21T06:00:48.602452-05:
  DOI: 10.1002/aoc.3967
Amino acid ionic liquid-based titanomagnetite nanoparticles: An efficient
and green nanocatalyst for the synthesis of
1,4-dihydropyrano[2,3-c]pyrazoles
- Authors: Davood Azarifar; Omolbanin Badalkhani, Younes Abbasi
  Abstract: The amino acid ionic liquid tetrabutylammonium asparaginate (TBAAsp) was immobilized on titanomagnetite (Fe3−xTixO4) nanoparticles in a facile one-pot process using an organosilane compound (TMSP) as spacer. The modified Fe3−xTixO4@TMSP@TBAAsp magnetic nanoparticles were characterized using Fourier transform spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, vibrating sample magnetometry and thermogravimetric analysis. The resulting analytical data clearly verified the successful immobilization of the ionic liquid on the magnetic substrate. The magnetic ionic liquid-based nanoparticles exhibited high catalytic activity in the synthesis of 1,4-dihydropyrano[2,3-c]pyrazole derivatives via a one-pot three-component reaction under mild reaction conditions. The catalyst was easily recycled and reused for at least six runs without any considerable loss of activity.Tetrabutylammonium asparaginate (TBAAsp) ionic liquid-functionalized titanomagnetite (Fe3−xTixO4@TMSP@TBAAsp) nanoparticles as an efficient and recyclable heterogeneous nanocatalyst were synthesized via a simple procedure for the first time. The prepared catalyst was fully characterized. Catalytic activity of this green catalyst was explored for one-pot three-component synthesis of dihydropyrano[2,3-c]pyrazoles under solvent-free conditions.
  PubDate: 2017-07-21T05:56:38.527075-05:
  DOI: 10.1002/aoc.3949
Synthesis and spectroscopic characterizations of Cu(II) complexes with
novel 15-membered N4 macrocyclic ligand and their utility to obtain CuO
nanostructures for efficient degradation of dyes
- Authors: Abdel Majid A. Adam; A. Alhadhrami, Hosam A. Saad, Moamen S. Refat
  Abstract: This paper describes synthesis, characterization and application of a series of Cu(II) complexes with a novel 3-thioxo-[1,2,4,5]tetrazocane-6,8-dione (N4) macrocyclic ligand. The complexes were characterized by physicochemical and spectroscopic techniques, such as UV–visible and IR spectroscopies, molar conductance, magnetic susceptibility measurements, and elemental analysis. The data suggest that the mononuclear Cu(II) complexes have a metal-to-ligand mole ratio of 1:1 and that the Cu(II) ions are coordinated with the four nitrogen atoms inside the N4 macrocyclic ring. The experimental anisotropic g-values indicate that the chloro, nitrato, acetate, and perchlorato complexes have six-coordinate distorted octahedral behavior, whereas the sulfato complex has five-coordinate square-pyramidal geometry. A simple and nontoxic method for preparation of CuO nanoparticles based upon the thermal decomposition of the synthesized Cu(II) complexes has been explored. Finally, the degradation of Rhodamine 6G dye by the catalytic performance of nano-sized CuO material has been evaluated.A novel 15-membered N4 macrocyclic ligand was prepared. The direct thermal decomposition of the nitrato Cu(II) complex with this ligand leads to a CuO material with an unusual ice shovel-like-shaped morphology involving a highly organized nanoscale structure.
  PubDate: 2017-07-21T05:56:18.932548-05:
  DOI: 10.1002/aoc.3950
Phosphated tungstate: An efficient new solid phosphoric acid catalyst for
the synthesis of heterocyclic nitrones
- Authors: Alireza Banan; Hassan Valizadeh, Akbar Heydari, Abolghasem Moghimi
  Abstract: Phosphated tungstate as a new, reusable and efficient solid phosphoric acid catalyst was synthesized and used to promote the reaction of diaminoglyoxime with various aromatic aldehydes. The prepared phosphated tungstate was characterized using various techniques including X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy and thermal analysis. A wide variety of heterocyclic nitrones were obtained under mild reaction conditions and in high yields by using the prepared catalyst.Phosphated tungstate as a new, reusable and efficient solid phosphoric acid catalyst was synthesized, and to promote the reaction of diaminoglyoxime with various aromatic aldehydes. A wide variety of heterocyclic nitrones were obtained under mild reaction conditions and in high yields.
  PubDate: 2017-07-21T05:50:45.472423-05:
  DOI: 10.1002/aoc.3944
Sulfuric acid heterogenized on magnetic Fe3O4 nanoparticles: A new and
efficient magnetically reusable catalyst for condensation reactions
- Authors: Lotfi Shiri; Setare Zarei, Mosstafa Kazemi, Davood Sheikh
  Abstract: Immobilized sulfuric acid on magnetic Fe3O4 nanoparticles (Fe3O4 MNPs-OSO3H) as a new solid acid nanocomposite was successfully synthesized and its catalytic activity in a series of condensation reactions was studied. High catalytic activity, simple separation from reaction mixture by an external magnet and good reusability are several eco-friendly advantages of this catalytic system. It is noteworthy that this catalytic system is applicable to a wide range of spectrum of aromatic aldehydes, and the desired products were obtained in good to excellent yields under mild conditions. The use of ecofriendly solvents makes also this synthetic protocol ideal and fascinating from the environmental point of view.Sulfuric acid heterogenized on magnetic Fe3O4 nanoparticles (Fe3O4 MNPs-OSO3H) was found to be a novel, eco-friendly and versatile magnetically recoverable catalyst for the condensation reactions.
  PubDate: 2017-07-21T05:45:50.423418-05:
  DOI: 10.1002/aoc.3938
Anti-proliferative activity of newly synthesized cd(II), cu(II),
Zn(II),Ni(II), co(II), VO(II), and Mn(II) complexes of
2-((4,9-dimethoxy-5-oxo-5H-furo[3,2-g]chromen-6-yl)methylene)
hydrazinecarbothioamide on three human cancer cells
- Authors: Mohamad M.E. Shakdofa; Hanan A. Mousa, Ahmed M.A. Elseidy, Ammar A. Labib, Mamdouh M. Ali, Amira S. Abd-El-All
  Abstract: Thiosemicarbazone ligand, 2-((4,9-dimethoxy-5-oxo-5H-furo[3,2-g]chromen-6-yl)methylene) hydrazinecarbothioamide and its Cd(II), Cu(II), Zn(II), Ni(II), Co(II), VO(II), and Mn(II) complexes have been prepared and characterized by various spectroscopic and analytical techniques. Complexes molar conductance measurements displayed that all complexes (2–8) are non-electrolyte. With general composition [M(H3L)(CH3COO)2H2O].nH2O, where M = Cd(II), Cu(II), Zn(II), Ni(II), Co(II) and Mn(II) while complex (8) has [VO(H3L)(SO4)H2O].2H2O formula. Based on analytical and spectral measurements, the octahedral or distorted octahedral geometries suggested for complexes. Ligand and complexes anti-proliferative activities were assessed against three various human tumor cell lines including breast cancer (MCF-7), liver cancer (HepG2) and lung cancer (A549) using SRB fluorometric assay and cis-platin as positive control. The anti-proliferative activity result indicated that the ligand and its complexes have considerable anti-proliferative activity analogous to that of ordinarily utilized anti-cancer drug (cis-platin). They do their anti-cancer activities by modifying free radical's generation via raising the superoxide dismutase activity and depletion of intracellular reduced glutathione level, catalase, glutathione peroxidase activities, escorted by highly generation of hydrogen peroxide, nitric oxide and other free radicals leading to tumor cells death, as monitoring by decreasing the protein and nucleic acids synthesis.Cd(II), Cu(II), Zn(II), Ni(II), Co(II), VO(II), and Mn(II) complexes of 2-((4,9-dimethoxy-5-oxo-5H-furo[3,2-g]chromen-6-yl) methylene) hydrazinecarbothioamide have considerable anti-proliferative activity against human breast cancer (MCF-7); human liver cancer (HepG2) and human lung cancer (A549) analogous to the activity of ordinarily utilized anticancer drug (cisplatin).
  PubDate: 2017-07-21T05:40:25.436325-05:
  DOI: 10.1002/aoc.3936
Synthesis, characterization and computational study of CuI nanoparticles
immobilized on modified poly (styrene-co-maleic anhydride) as a green,
efficient and recyclable heterogeneous catalyst in the synthesis of
1,4-disubstituted 1,2,3-triazoles via click reaction
- Authors: Fatemeh Ebrahimpour-Malamir; Tayebeh Hosseinnejad, Razieh Mirsafaei, Majid M. Heravi
  Abstract: Poly (styrene-co-maleic anhydride) (SMA) was modified by reactionwith4-amino-2-methyl-10H-thiene [2,3-b][1,5]-benzodiazepine (ATD) hydrochloride, providing an imide with the appropriate sites for the coordination of Cu(I)ions. This modified SMA was reacted with CuI to obtain immobilized Cu(I) NPs. This Cu(I) NPs (CuI/SMI-TD) was fully characterized by conventional techniques such as FT-IR, NMR, SEM, TEM, EDAX and ICP-AES analysis. The SEM and TEM images clearly showed CuI NPs as spherical shapes and the size of particles is 30-60 nm. Moreover, a quantitative description for experimental features of CuI/SMI-TD was presented via computational assessment for the interactions between copper metal ions and coordination sites of SMI-TD ligand. The catalytic activity of this new catalyst was examined in the regioselective synthesis of 1,4-disubstituted-1,2,3 triazoles in a classical copper-catalyzed reaction a so-called click reaction. The catalyst showed highly efficient catalytic activity, excellent reusability, high yield and more importantly excellent, regioselectivity. The catalyst was recoverable through simple filtration and can be reused at least five times without significant loss of catalytic activity. The heterogeneous nature of the catalyst was confirmed based on the hot filtration test and ICP-AES analysis.A novel heterogeneous catalyst based on copper (I) supported on modified SMA has been synthesized and characterized. This catalyst exhibits excellent catalytic activities in synthesis of 1,4-disubstituted 1,2,3-triazoles via click reaction.
  PubDate: 2017-07-21T05:31:12.540269-05:
  DOI: 10.1002/aoc.3913
Three Arene-Ru(II) compounds of 2-halogen-5-aminopyridine: Synthesis,
characterization, and cytotoxicity
- Authors: Xiao-Wei Yan; Yong-Rong Xie, Zhi-Min Jin, Mao-Lin Hu, Liang-Pu Zhou
  Abstract: Three novel compounds, (η6-p-cymene)RuCl2(2-fluoro-5-aminopyridine) (compound 1), (η6-p-cymene)RuCl2(5-amino-2-chlorpyridine) (compound 2) and (η6-p-cymene)RuCl2(2-bromo- 5-aminopyridine) (compound 3), were synthesized and characterized. The compound 1 and 3 were determined by X-ray diffraction, showing a distorted piano-stool type of geometry with similar bond lengths and angles around the ruthenium. Compound 2 exhibited moderate in vitro activity against A549 and MCF-7 human cancer cells, the other two lower activities. The UV–vis and fluorescent absorption titrations showed that three compounds binded with CT-DNA in a minor groove. The intrinsic binding constants (Kb) were calculated to be 2.13(±0.03) × 105 M−1, 2.89(±0.03) × 105 M−1 and 2.45(±0.03) × 105 M−1 for compound 1, 2 and 3, respectively, by using UV–vis absorption titrations data. Among the three compound, the highest value of intrinsic binding constant of compound 2 was consistent with its highest cytoxicity against A549 and MCF-7 human cancer cells in vitro.Three novel compounds, (η6-p-cymene)RuCl2(2-X-5-aminopyridine) (X = F, Cl, Br), were synthesized and characterized. The X-ray diffraction revealed that the molecules containing substitutional F and Br atom showed a distorted piano-stool type of geometry. The UV-vis and fluorescent absorption titrations showed that three compounds binded with CT-DNA in a minor groove. The intrinsic binding constants (Kb) were 2.13(±0.03)×105 M−1, 2.89(±0.03) ×105 M−1 and 2.45(±0.03)×105 M−1 for compound containing substitutional F, Cl and Br atom, respectively. Among the three compounds, the highest value of intrinsic binding constant of compound containing substitutional Cl atom was consistent with its highest cytoxicity against A549 and MCF-7 human cancer cells in vitro.
  PubDate: 2017-07-20T03:32:37.218718-05:
  DOI: 10.1002/aoc.3923
An efficient synthesis and cytotoxic activity of
2-(4-chlorophenyl)-1H–benzo[d]imidazole obtained using a magnetically
recyclable Fe3O4 nanocatalyst-mediated white tea extract
- Authors: Sara Shojaee; Mahnaz Mahdavi Shahri
  Abstract: A simple and efficient procedure has been developed for the synthesis of biologically relevant 2-substituted benzimidazoles through a one-pot condensation of o-phenylenediamines with aryl aldehydes catalysed by iron oxide magnetic nanoparticles (Fe3O4 MNPs) in short reaction times with excellent yields. In the present study, Fe3O4 MNPs synthesized in a green manner using aqueous extract of white tea (Camelia sinensis) (Wt-Fe3O4 MNPs) were applied as a magnetically separable heterogeneous nanocatalyst to synthesize 2-(4-chlorophenyl)-1H–benzo[d]imidazole which has potential application in pharmacology and biological systems. Fourier transform infrared and NMR spectroscopies were used to characterize the 2-(4-chlorophenyl)-1H–benzo[d]imidazole. In vitro cytotoxicity studies on MOLT-4 cells showed a dose-dependent toxicity with non-toxic effect of 2-(4-chlorophenyl)-1H–benzo[d]imidazole, up to a concentration of 0.147 µM. The green synthesized Wt-Fe3O4 MNPs as recyclable nanocatalyst could be used for further research on the synthesis of therapeutic materials, particularly in nanomedicine, to assist in the treatment of cancer.In this research, the green synthesized Fe3O4 MNPs using aqueous extract of white tea has been applied as magnetically separable heterogeneous nanocatalyst to synthesize 2-(4-Chlorophenyl)-1 H benzo [d] imidazole which has potential application in pharmacology and biological systems. The present study successfully demonstrated a simple, eco-friendly method for the imidaozol with significant potential anticancer properties.
  PubDate: 2017-07-20T03:32:05.501733-05:
  DOI: 10.1002/aoc.3934
Synthesis of ferrocene-modified poly(glycidyl methacrylate) and its
burning rate catalytic property
- Authors: Weidong Zhou; Li Wang, Haojie Yu, Xia Xia
  Abstract: A series of ferrocene-modified poly(glycidyl methacrylate) (PGMA-Fc) compounds were synthesized and applied as burning rate catalysts in simulative solid propellant to overcome migration problems. 1H NMR and Fourier transform infrared spectroscopies and gel permeation chromatography were used to characterize the synthesized polymers. Their electrochemical behavior was evaluated using cyclic voltammetry. Their catalytic performance for the decomposition of ammonium perchlorate (AP) was investigated using thermogravimetric analysis. Anti-migration studies were conducted in migration tubes under 50°C. The results show that PGMA-Fc has a good catalytic effect on lowering the thermal decomposition temperature of AP. Anti-migration studies show that PGMA-Fc has better anti-migration performance than ferrocene and catocene.A series of ferrocene-modified poly(glycidyl methacrylate) (PGMA-Fc) compounds were synthesized and applied as burning rate catalysts in simulative solid propellant to overcome migration problems. Anti-migration studies show that PGMA-Fc has a good catalytic effect on lowering the thermal decomposition temperature of AP and better anti-migration performance than ferrocene and catocene.
  PubDate: 2017-07-20T03:25:55.907416-05:
  DOI: 10.1002/aoc.3932
Synthesis and characterization of SnO2/(NH4)2-SnCl6 nanocomposites loaded
on activated carbon and its application for adsorption of methylene Blue
and Orange G
- Authors: Samane Jalali; Mahmood Reza Rahimi, Mehrorang Ghaedi, Arash Asfaram, Alireza Goudarzi
  Abstract: The present study deals with the synthesis and characterization (FE-SEM, particle size distribution, XRD and point of zero charge) SnO2/(NH4)2-SnCl6 nanocomposites loaded on activated carbon (SnO2/(NH4)2-SnCl6-NCs-AC) and its subsequent application for the simultaneous removal of Methylene Blue (MB) and Orange G (OG) from aqueous solution. Response surface methodology (RSM) based on central composite design (CCD) give trend of influencing responses with respect to five parameters such as contact time (X1), OG concentration (X2), MB concentration (X3), adsorbent mass (X4) and pH (X5). In later stage following recognition of significant variables and interaction, quadratic model generated which are able to predict the dyes removal in different conditions. Justification and selection of significant terms was conducted based on analysis of variance and Fisher's F-test Optimal value of contact time, OG concentration, MB concentration, adsorbent mass and pH were set at 4.0 min, 10 mg l−1, 20 mg L−1, 0.015 g and 6.0, respectively, which lead to achievement of best experiment removal percentage of 97.0 and 99.5% OG and MB respectively, from their binary solutions. The whole experimental data follow pseudo-first-order and pseudo-second-order rate equations. The fitting experimental data to more available conventional model like Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models revel more ability of Langmuir model (with R2 > 0.997) for explanation of system in equilibrium. The adsorption efficiency remained high even after the five cycle of reuse (99.76% and 95.56% for MB and OG, respectively).The present study deals with the synthesis and characterization SnO2/(NH4)2-SnCl6 nanocomposites loaded on activated carbon (SnO2/(NH4)2-SnCl6-NCs-AC) and its subsequent application for the simultaneous removal of Methylene Blue and Orange G from aqueous solution.
  PubDate: 2017-07-20T03:21:46.129491-05:
  DOI: 10.1002/aoc.3903
Issue Information
- Abstract: No abstract is available for this article.
  PubDate: 2017-07-19T03:57:19.798171-05:
  DOI: 10.1002/aoc.3619
Cover Image
- Authors: Fayaz Ali Larik; Aamer Saeed, Tanzeela Abdul Fattah, Urooj Muqadar, Pervaiz Ali Channar
  Abstract: The cover image, by Fayaz Ali Larik et al., is based on the Review Article Recent advances in the synthesis, biological activities and various applications of ferrocene derivatives,
  DOI : 10.1002/aoc.3664.
  PubDate: 2017-07-19T03:57:16.876519-05:
Preparation of chitosan functionalized end-capped Ag-NPs and composited
with Fe3O4-NPs: Controlled release to pH-responsive delivery of
progesterone and antibacterial activity against pseudomonas aeruginosa
(PAO-1)
- Authors: Faezeh Pourebrahim; Mehrorang Ghaedi, Kheibar Dashtian, Shadi Kheirandish, Ramin Jannesar, Vahid Pezeshkpour
  Abstract: In this work, functionalized chitosan end-capped Ag nanoparticles (NPs) and composited with Fe3O4-NPs was prepared as pH-responsive controlled release carrier for gastric-specific drug delivery. The structure of prepared material was characterized by FE-SEM, XRD, EDS and FT-IR analysis. The loading behavior of the progesterone onto this novel material was studied in aqueous medium at 25°C and their release was followed spectrophotometrically at 37°C in seven different buffer solutions (pH 1.2, 2.2, 3.2, 4.2, 5.2, 6.2 and 7.2) to simulate intestine and gastric media which experimental results reveal more release rate in pH 1.2 (gastric medium) with respect to other buffers. This observation is attributed to dependency of the CS-IMBDO-Ag-Fe3O4-NPs and progesterone structure with buffer pH that candidate this new material as prospective pH-sensitive carrier for gastric-targeted drug delivery. On the other hand, the antibacterial properties of this material against gram-negative bacterium pseudomonas aeruginosa (PAO-1) in agar plates was studied and accordingly based on broth micro dilution the minimum bactericidal concentration (MBC) and minimum inhibitory concentration (MIC) with respect to standard CLSI in different concentrations of CS-IMBDO-Ag-Fe3O4-NPs was calculated. The results reveal that MIC and MBC values are 50 and 1250 μg/mL, respectively. In addition, extracts of Portulaca oleracea leaves was prepared and its antibacterial activity in single and binary system with CS-IMBDO-Ag-Fe3O4-NPs as synergies effect against PAO-1 was tested and results shown that these materials have significant synergistic effect for each other.Functionalized chitosan end-capped Ag nanoparticles (NPs) composited with Fe3O4-NPs was prepared and characterized by FE-SEM, EDS and FT-IR analysis. The loading behavior of the progesterone onto this novel material was studied in aqueous medium at 25 °C and their release was followed spectrophotometrically some different solutions (buffered at pH 1.2, 2.2, 3.2, 4.2, 5.2,6.2 and 7.2) to simulate intestine and gastric media. The release rate in pH 1.2 (gastric medium) buffer is higher than that other buffers. Also, we investigated the antibacterial properties of this material against gram-negative bacterium pseudomonas aeruginosa (PAO-1) in agar plates.
  PubDate: 2017-07-16T23:37:15.312583-05:
  DOI: 10.1002/aoc.3921
Copper nanoparticles incorporated on a mesoporous carbon nitride, an
excellent catalyst in the Huisgen 1,3-dipolar cycloaddition and
N-arylation of N-heterocycles
- Authors: Siyavash Kazemi Movahed; Parinaz Salari, Melika Kasmaei, Mahsa Armaghan, Minoo Dabiri, Mostafa M. Amini
  Abstract: Cu nanoparticles with average particles size around 10 nm were incorporated on the surface of a mesoporous carbon nitride support. The XRD and N2 adsorption isotherms show that it maintains a hexagonal mesoporous structure with a high surface area (600.03 m2 g−1). The embedded Cu nanoparticles exhibit extremely high catalytic performance in two different kinds of organic reactions. The Huisgen 1,3-dipolar cycloaddition and N-arylation of N-heterocycles were all accomplished.Copper nanoparticles around 10 nm were incorporated on the surface of a mesoporous carbon nitride support. The Huisgen 1,3-dipolar cycloaddition and N-arylation of N-heterocycles were all successfully accomplished.
  PubDate: 2017-07-16T23:01:19.198276-05:
  DOI: 10.1002/aoc.3914
Structural studies and biological activity evaluation of Pd(II), Pt(II)
and Ru(II) complexes containing N-phenyl, N`-(3-triazolyl)thiourea
- Authors: Ahmed M. Mansour
  Abstract: [MCl(H2L)(OH2)]·1.5H2O (M = Pd(II) (1) and Pt(II) (2)) and [Ru(H2L)2(OH2)2]·3H2O (3) (H3L: N-phenyl, N`-(3-triazolyl)thiourea) were synthesized, characterized and tested for their antibacterial activities against Staphylococcus aureus and Escherichia coli bacteria. The thiourea derivative is coordinated to Mn+ ions as a mono-negatively N,S-bidentate ligand via the enolization of C = S group and triazole N center. The density functional theory calculations reveal that presence of a water molecule in a trans position to triazole ring increased the stability of d8 metal ions complexes via the formation of strong Cl…NH intramolecular H-bond. The cis-Ru(II)-isomer with two isoenergetically H2L− molecules are more stable than the trans-analog. Coordination of H3L to Ru(II) ion did not alter the toxicity of the free ligand, while the interaction with the d8 metal ions gave rise to inactive compounds.DFT calculations reveal that presence of H2O, in the coordination spheres of Pd(II) and Pt(II) complexes of the title ligand, in a trans-position to the triazole ligand with increase the stability via the formation of strong Cl…NH hydrogen bond. Alternatively, the cis-isomer of Ru(II) complex is more stable than the trans-analog. The ligand interacts with the metal ions via the enolization of NH-C = S- group and triazole nitrogen atom as evidenced by the analytical and spectral tools.
  PubDate: 2017-07-11T02:35:49.738992-05:
  DOI: 10.1002/aoc.3928
Synthesis of innovative biochemical active mixed ligand metal(II)
complexes with thiazole containing Schiff base: In vitro antimicrobial
profile
- Authors: Natarajan Raman; Thiravidamani Chandrasekar, Ganesan Kumaravel, Liviu Mitu
  Abstract: An unique Schiff base ligand, formed by the condensation reaction of 2-aminobenzothiazole with curcumin and its Cu(II), Ni(II), Co(II) and Zn(II) complexes incorporating 2,2′-bipyridine as coligand were synthesised. They were characterized via analytical and spectroscopic methods. The complexes adopt square planar geometry. Their antimicrobial activity and photocatalytic efficiency on Congo red dye molecule were explored. It is found that all the complexes are antimicrobial active and show higher activity than the ligand. The nuclease activity of the above metal complexes was also assessed by absorption titration, fluorescence, viscosity and gel electrophoresis assay. The complexes bind CT DNA through intercalation mode. The data reveal that the above synthesised metal(II) complexes are found to be effective metallonucleases. The gel electrophoresis results exhibit that the metal complexes cleave pBR322 plasmid DNA in presence of hydrogen peroxide effectively compared to the ligand. The synthesised metallonucleases should lead to a new era for the logical sketch of dominant agents for probing and targeting nucleic acids. This exploration reveals that Cu(II) complex has a valued biological and photochemical profile.A few novel mixed ligand metal(II) complexes were synthesized by the condensation of curcumin based Schiff base with 2-aminobenzothiazole and 2,2'-bipryidine and characterized by spectral and analytical data. They are identified as strong metallointercalators, potent DNA unfolding agents and have better biological profile. The complexes were also subjected to photocatalytic activity and inferred as potential catalysts for the degradation of Cango red dye. Among the metal complexes copper(II) complex has deserving biochemical profile.
  PubDate: 2017-07-07T05:00:51.929107-05:
  DOI: 10.1002/aoc.3922
Diethyldisulfoammonium chlorometallates as heterogeneous Brønsted–Lewis
acidic catalysts for one-pot synthesis of
14-aryl-7-(N-phenyl)-14H-dibenzo[a,j]acridines
- Authors: Arup Kumar Dutta; Pinky Gogoi, Ruli Borah
  Abstract: A new series of Brønsted–Lewis acidic diethyldisulfoammonium chlorometallates, [DEDSA][FeCl4] and [DEDSA]2[Zn2Cl6], were synthesized as solid materials from the reaction of [(Et)2N(SO3H)2][Cl] ionic liquid with transition metal chlorides (FeCl3 and ZnCl2) at 80 °C in neat condition for 2 h. The chlorometallates were fully characterized using various spectroscopic and analytical techniques such as Fourier transform infrared, UV–visible and Raman spectroscopies, powder X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray and thermogravimetric analyses, Hammett acidity and elemental analyses. Their catalytic activity was studied as reusable heterogeneous catalysts for the three-component synthesis of novel 14-aryl-7-(N-phenyl)-14H-dibenzo[a,j]acridines under solvent-free conditions at 100 °C.Two Brønsted-Lewis acidic solid diethyl-disulfoammonium chlorometallates [DEDSA][FeCl4] and [DEDSA]2[Zn2Cl6] were synthesized from the reaction of [(Et)2N(SO3H)2][Cl] ionic liquid with transition metal chlorides (FeCl3 and ZnCl2) at 80 °C and evaluated as reusable heterogeneous catalyst for preparation of novel 14-aryl-7-(N-phenyl)-14H-dibenzo[a,j]acridines without solvent at 100 °C .The chlorometallates were confirmed by FT-IR, UV/Vis, Raman, PXRD, SEM-EDX, TGA, Hammett acidity and elemental analyses.
  PubDate: 2017-07-07T04:55:55.346066-05:
  DOI: 10.1002/aoc.3900
Antimicrobial and anticancer activities of Schiff base ligand and its
transition metal mixed ligand complexes with heterocyclic base
- Authors: H. F. Abd El-Halim; Gehad G. Mohamed, Mahmoud N. Anwar
  Abstract: A new Schiff base ligand (HL) was prepared via a condensation reaction of quinoline-2-carboxaldhyde with 2-aminophenol in a molar ratio of 1:1. Its transition metal mixed ligand complexes with 1,10-phenanthroline (1,10-phen) as co-ligand were also synthesized in a 1:1:1 ratio. HL and its mixed ligand complexes were characterized using elemental analysis, infrared, 1H NMR, mass and UV–visible spectroscopies, molar conductance, magnetic measurements, solid reflectance, thermal analysis, electron spin resonance and X-ray diffraction. Molar conductance measurements showed that all complexes have an electrolytic nature, except Cd(II) complex. From elemental and spectral data, the formulae [M(L)(1,10-phen)(H2O)]Clx⋅nH2O (where M = Cr(III) (x = n = 2), Mn(II) and Ni(II) (x = 1, n = 2), Fe(III) (x = n = 2), Co(II), Cu(II) and Zn(II) (x = 1, n = 2)) and [Cd(L)(1,10-phen)Cl]⋅3H2O for the metal complexes have been proposed. The geometric structures of complexes were found to be octahedral. Powder X-ray diffraction reflected the crystalline nature of the complexes; however, the Schiff base is amorphous. HL and its mixed ligand complexes were screened against Gram-positive bacteria (Streptococcus pneumoniae and Bacillus subtilis) and Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli). Antifungal activity was determined against Aspergillus fumigatus and Candida albicans, the data showing that most complexes had activity less than that of the Schiff base while Mn(II), Fe(III) and Ni(II) complexes showed no significant antifungal activity. The anticancer activity of HL and its metal complexes was also studied against breast and colon cell lines. The metal complexes showed IC50 higher than that of HL, especially the Cu(II) complex which showed the highest IC50 against breast cell line.The relation between M─O bond strength and inhibition zone diameter of metal complexes.
  PubDate: 2017-07-07T04:55:25.272053-05:
  DOI: 10.1002/aoc.3899
Biohybrid based on layered terbium hydroxide and applications as drug
carrier and biological fluorescence probe
- Authors: Ruijun Ju; Qingyang Gu
  Abstract: Aspirin (abbr. ASA) is intercalated into the layered terbium hydroxide (LTbH) by anion exchange method. Structure, chemical compositions, thermostability, morphology, luminescence property, cytotoxic effects and controlled-release behaviors have been investigated. The ASA molecules may embed between layers with monolayered vertical arrangement, and the thermal stability of organics was enhanced after intercalation. The Tb3+ luminescence in ASA-LTbH composites was enhanced compared with LTbH precusor and the luminescence intensity increased with the deprotonation degree. The cytotoxic effect of LTbH was observed with a sulforhodamine B (SRB) colorimetric assay, which revealed that the LTbH showed low cytotoxic effects. In addition, the ASA-LTbH composites exhibited a sustained release of ASA in Na2HPO4-NaH2PO4 buffer solution at pH 6.86 and 37°C. Construction of LRHs composites with drug molecules provided a beneficial pathway for preparing biohybrid based on LRHs, which may have potential applications in drug delivery carrier and biological fluorescence probe.Intercalation of aspirin (APC) into layered terbium hydroxide (LTbH) to form composites. The composites show excellent pharmaceutical properties and luminescence properties, which may have potential applications in drug carrier and biological fluorescence probe.
  PubDate: 2017-07-07T04:50:40.449535-05:
  DOI: 10.1002/aoc.3926
Synthesis of nanomagnetic supported thiourea–copper(I) catalyst and its
application in the synthesis of triazoles and benzamides
- Authors: Leila Mohammadi; Mohammad Ali Zolfigol, Ardeshir Khazaei, Meysam Yarie, Samira Ansari, Saeid Azizian, Maryam Khosravi
  Abstract: A novel nanomagnetic supported thiourea–copper(I) complex and inorganic–organic Takemoto-like hybrid nanomagnetic catalyst was designed, and synthesized. The prepared naomagnetic catalyst was characterized using Fourier transform infrared spectroscopy, X-ray diffraction, energy-dispersive X-ray analysis, transmission and scanning electron microscopies, thermogravimetry, nitrogen adsorption/desorption, zeta potential and vibrating sample magnetometry. Furthermore, the fabricated dual-role inorganic–organic hybrid catalyst shows a striking and robust catalytic activity for the synthesis of triazoles and benzamides through click and coupling reactions, respectively, under mild and eco-friendly reaction conditions.A novel inorganic–organic Takemoto-like hybrid nanomagnetic catalyst was constructed. The structural verification of the new catalyst was fully made by applying various methods. The fabricated dual-role hybrid catalyst showed striking and robust catalytic activity for the synthesis of triazoles and benzamides through click and coupling reactions, respectively, under mild and eco-friendly reaction conditions.
  PubDate: 2017-07-07T03:56:08.143194-05:
  DOI: 10.1002/aoc.3933
Simultaneous removal of Cu2+ and Cr3+ ions from aqueous solution based on
Complexation with Eriochrome cyanine-R and derivative spectrophotometric
method
- Authors: Ahmad Reza Bagheri; Mehrorang Ghaedi, Kheibar Dashtian, Shaaker Hajati, Ali Akbar Bazrafshan
  Abstract: TiO2 nanoparticles deposited on activated carbon (TiO2–NP–AC) was prepared and characterized by XRD and SEM analysis. Subsequently, simultaneous ultrasound-assisted adsorption of Cu2+ and Cr3+ ions onto TiO2-NPs-AC after complexation via eriochrome cyanine R (ECR) has been investigated with UV–Vis and FAA spectrophotometer. Spectra overlapping of the ECR-Cu and ECR-Cr complex was resolve by derivative spectrophotometric technique. The effects of various parameters such as initial Cu2+ (A) and Cr3+ (B) ions concentrations, TiO2-NPs-AC mass (C), sonication time (D) and pH (E) on the removal percentage were investigated and optimized by central composite design (CCD). The optimize conditions were set as: 4.21 min, 0.019 mg, 20.02 and 13.22 mg L−1 and 6.63 for sonication time, TiO2–NP–AC mass, initial Cr3+ and Cu2+ ions concentration and pH, respectively. The experimental equilibrium data fitting to Langmuir, Freundlich, Temkin and Dubinin–Radushkevich models show that the Langmuir model is a good and suitable model for evaluation and the actual behavior of adsorption process and maximum adsorption capacity of 105.26 and 93.46 mg g−1 were obtained for Cu2+ and Cr3+ ions, respectively. Kinetic evaluation of experimental data showed that the adsorption processes followed well pseudo second order and intraparticle diffusion models.TiO2 nanoparticles deposited on activated carbon (TiO2–NP–AC) was prepared and characterized by XRD and SEM analysis. Subsequently, simultaneous ultrasound-assisted adsorption of Cu2+ and Cr3+ ions onto TiO2-NPs-AC after complexation via eriochrome cyanine R (ECR) has been investigated with UV–Vis and FAA spectrophotometer. Spectra overlapping of the ECR-Cu and ECR-Cr complex was resolve by derivative spectrophotometric technique.
  PubDate: 2017-07-07T03:46:03.304041-05:
  DOI: 10.1002/aoc.3918
Synthesis of soluble and meltable pre-ceramic polymers for Zr-containing
ceramic nanocomposites
- Authors: Xin Long; Changwei Shao, Jun Wang, Yanzi Gou
  Abstract: Polymer-derived methods are one of the most important tools for the synthesis of ceramics with a finely dispersed microstructure. In this study, a soluble and meltable ZrC/C pre-ceramic polymer, P-DACZ, (which would later exhibit a high ceramic yield of 71 wt%) was synthesized via radical polymerization. By adding low molecular weight polycarbosilane in any proportion during the radical polymerization process of P-DACZ, a soluble and meltable ZrC/SiC/C pre-ceramic precursor, PCS-DACZ (which would later exhibit a high ceramic yield of>80 wt%) was synthesized. After annealing at 1400 °C under an argon flow, the precursors converted into bulk ZrC/C and ZrC/SiC/C ceramic nanocomposites. The ZrC nanoparticles could resist any grain growth when heat-treated at temperatures above 1800 °C because the C or SiC matrix prevented long-range atomic diffusion of zirconium. Such ceramic nanocomposites would be suitable for structural and (multi)functional applications at harsh environments with high temperatures.The synthesized soluble and meltable pre-ceramic polymers can convert into bulk ZrC/C and ZrC/SiC/C ceramic nanocomposites after annealing at 1400 °C under an argon flow. The ZrC nanoparticles could resist any grain growth when heat treated at temperatures above 1800 °C because the C or SiC matrix prevented long range atomic diffusion of zirconium.
  PubDate: 2017-07-05T03:11:15.699372-05:
  DOI: 10.1002/aoc.3942
N-(3-silyl propyl) diethylene triamine N,N',N''-tri-sulfonic acid
immobilized on Fe3-xTixO4 magnetic nanoparticles: A new recyclable
heterogeneous nanocatalyst for the synthesis of hexahydroquinolines
- Authors: Davood Azarifar; Younes Abbasi, Omolbanin Badalkhani
  Abstract: In the present study, for the first time N-(3-silyl propyl) diethylene triamine N,N',N''-tri-sulfonic acid (SPDETATSA) was grafted on magnetic Fe3-xTixO4 nanoparticles. The structure of the resulted nanoparticles was characterized based on Fourier-transform infrared (FT-IR), energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermal gravimetric analysis (TGA), and vibrating sample magnetometer (VSM) analyses. The results confirmed the successful immobilization of sulfamic acid groups onto the magnetic support. These nanoparticles exhibited high catalytic activity as novel magnetically recyclable acid nanocatalyst in the synthesis of a diverse range of hexahydroquinolines through one-pot tandem reactions in excellent yields. Also, this nanocatalyst performed satisfactory catalytic maintenance of activity for the synthesis of the reaction products after 4 rounds of recycling with no considerable loss of activity.For the first time N-(3-silyl propyl) diethylene triamine N,N',N''-tri-sulfonic acid (SPDETATSA) was grafted on magnetic Fe3-xTixO4 nanoparticles. The structure of the resulted nanoparticles was characterized based on FT-IR, EDX, SEM, TEM, TGA and VSM techniques. These nanoparticles exhibited high catalytic activity in synthesis of hexahydroquinolines from tandem reactions in excellent yields.
  PubDate: 2017-07-05T03:05:56.639567-05:
  DOI: 10.1002/aoc.3939
Supported copper (I) catalyst from fish bone waste: An efficient, green
and reusable catalyst for the click reaction toward N-substituted
1,2,3-TRIAZOLES
- Authors: Xingquan Xiong; Zhongke Tang, Zhaohong Sun, Xiaoqing Meng, Sida Song, Zhilong Quan
  Abstract: An eco-efficient, green, and multi-gram procedure is presented for one-pot multicomponent synthesis of N-substituted 1,2,3-triazoles by using waste fishbone powders supported CuBr (FBPs-CuBr) as catalyst. FBPs-CuBr is found to be an efficient heterogeneous catalyst and a series of 1,2,3-triazoles are obtained in moderate to excellent yields in water under MW irradiation (70–98%). It can be separated conveniently by a simple filtration and reused at least seven consecutive runs with a slight drop in the product yields. Furthermore, the desired product still could be obtained in 80% yield when the scale of the reaction was increased to 40.0 mmol.Waste fishbone powders supported CuBr (FBPs-CuBr) was developed for the synthesis of N-substituted 1, 2, 3-triazoles in good to excellent yields under microwave-assisted condition. The N-substituted 1, 2, 3-triazole in the model reaction could be prepared in 80% yield even when the reaction scale was increased to 40 mmol.
  PubDate: 2017-07-05T03:01:11.118749-05:
  DOI: 10.1002/aoc.3946
Click approach to the three-component synthesis of novel
β-hydroxy-1,2,3-triazoles catalysed by new (Cu/Cu2O) nanostructure as a
ligand-free, green and regioselective nanocatalyst in water
- Authors: Hadi Esmaeili-Shahri; Hossein Eshghi, Jalil Lari, Seyyed Amin Rounaghi
  Abstract: Copper nanostructures were produced as an effective and regioselective catalyst for the synthesis of 1,2,3-triazoles from a wide range of raw materials, such as sodium azide, epoxides and terminal alkynes, in water via a one-pot three-component click reaction. The new heterogeneous catalyst was prepared by a simple ball mill reduction of CuO with NaBH4 using a ball-to-powder weight ratio of 50:1 under air atmosphere at room temperature. The catalyst was fully characterized using scanning electron microscopy, energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy and X-ray diffraction. The copper nanostructures catalysed both ring opening and triazole cyclization steps. Products were obtained in high yields and short reaction times. The reactions were performed at ambient temperature in water as a green solvent. The Cu/Cu2O nanostructures revealed high reusability and high stability via a simple recycling process.1,4-Disubstituted 1,2,3-triazoles were synthesized from sodium azide, epoxides and terminal alkynes in water via a one-pot three-component click reaction. Cu/Cu2O nanostructures as a regioselective and reusable catalyst were used in the synthesis. This method has many advantages including the use of water as a green solvent under mild conditions.
  PubDate: 2017-07-05T03:00:38.53054-05:0
  DOI: 10.1002/aoc.3947
Magnetic Fe3O4 nanoparticles supported imine/Thiophene-nickel (II)
complex: A new and highly active heterogeneous catalyst for the synthesis
of polyhydroquinolines and 2, 3-dihydroquinazoline-4(1H)-ones
- Authors: Lotfi Shiri; Leili Heidari, Mosstafa Kazemi
  Abstract: A new magnetically separable nickel catalyst (Ni(NO3)2−Imine/Thiophene-Fe3O4@SiO2) was readily prepared and structurally characterized by Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDX), Vibrating sample magnetometer (VSM), X-Ray diffraction (XRD) and Atomic absorption spectroscopy (AAS). The Ni(NO3)2−Imine/Thiophene-Fe3O4@SiO2 exhibited efficient catalytic activity in the synthesis of 2,3-dihydroquinazoline-4(1H)-ones and polyhydroquinolines. Catalysis research under water and solvent-free conditions makes also this synthetic protocol ideal and fascinating from the environmental point of view. The catalyst can be magnetically recovered after the reaction and can be reused for many times without appreciable decrease in activity.Magnetic Fe3O4 nanoparticles supported Imine/Thiophene-nickel (II) complex (Ni(NO3)2−Imine/Thiophene-Fe3O4@SiO2) was shown to be a versatile and highly efficient reusable catalyst for the synthesis of polyhydroquinoline and 2,3-dihydroquinazoline-4(1H)-one derivatives.
  PubDate: 2017-07-05T02:55:52.748348-05:
  DOI: 10.1002/aoc.3943
Polymerization of graphene oxide nanosheet by using of aminoclay:
Electrocatalytic activity of its platinum nanohybrids
- Authors: S. Jafar Hoseini; Mehrangiz Bahrami, Mahnaz Maddahfar, Roghayeh Hashemi Fath, Mahmoud Roushani
  Abstract: This study describes the polymerization of graphene oxide (GO) nanosheet to reduced-GO-aminoclay (RGC) by covalent functionalization of chemically reactive epoxy groups on the basal planes of GO with amine groups of magnesium phyllosilicate clay (known as aminoclay). The resulting RGC sheets were characterized and applied to support platinum nanostructures at toluene/water interface. Pt nanoparticles (NPs) with diameters about several nanometers were adhered to RGC sheets by chemical reduction of [PtCl2(cod)] (cod = cis,cis-1,5-cyclooctadiene) complex. Catalytic activity of Pt NPs thin films were investigated in the methanol oxidation reaction. Cyclic voltammetry results exhibit that the Pt/reduced-GO (RGO) and Pt/RGC thin films showed improved catalytic activity in methanol oxidation reaction in comparison to other Pt NPs thin films, demonstrating that the prepared Pt/RGO and Pt/RGC thin films are promising catalysts for direct methanol fuel cell.In this study, we have compared the electrocatalytic activity of Pt/reduced graphene oxide and Pt/reduced graphene-clay thin films in methanol oxidation reaction that showed improved catalytic activity in comparison to other Pt nanoparticle thin films.
  PubDate: 2017-07-05T02:51:15.231724-05:
  DOI: 10.1002/aoc.3894
The composite catalysts of Cu/CuxO nanoparticles supported on the carbon
fibers were prepared for styrene oxidation reaction
- Authors: Hongchun Mu; Chunping Li, Jie Bai
  Abstract: In this paper a novel simple method for preparing two different catalysts with various-valences copper was reported. Carbon nanofibers supported copper-cuprous oxide nanoparticles (Cu-Cu2O NPs/CNFs) and copper oxide nanoparticles (CuO NPs/CNFs) through electrospinning, adsorption and reduction in the high-pressure hydrogenation and the high-temperature calcination methods. These catalysts were investigated by a series of characterizations and were applied in reaction in nitrogen atmosphere, which had a good catalytic activity and selectivity of benzaldehyde for the reaction. Above all, the new study has been certified clearly, in which Cu-Cu2O NPs/CNFs and CuO NPs/CNFs composite catalysts enhanced the generation of benzaldehydeand the excellent catalytic properties were exhibited.Two catalysts of Cu/Cu2O NPs/CNFs and CuO NPs/CNFs were formed by electrospunning, carbonization, immersing, high-pressure hydrogenation and high-temperature decomposition methods. These catalysts were applied for styrene oxidation reaction under nitrogen atmosphere which had a good catalytic activity and selectivity of benzaldehyde for the reaction. Above all, the new study that Cu/Cu2O NPs/CNFs and CuO NPs/CNFs composite catalysts were contributed to the generation of benzaldehyde has been certified clearly, and the excellent catalytic properties were exhibited to us.
  PubDate: 2017-07-05T02:46:10.654826-05:
  DOI: 10.1002/aoc.3890
Synthesis and characterization of sulfamic acid supported on Fe3O4
nanoparticles: A green, versatile and magnetically separable acidic
catalyst for oxidation reactions and Knoevenagel condensation
- Authors: Lotfi Shiri; Hojatollah Narimani, Mosstafa Kazemi
  Abstract: Sulfamic acid immobilized on diethylenetriamine functionalized Fe3O4 nanoparticles (SA-DETA-Fe3O4) was successfully prepared and characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometer (VSM), thermo gravimetric analysis (TGA), X-Ray diffraction (XRD) and scanning electron microscopy (SEM). The sulfamic acid was found as a magnetically separable and highly active catalyst for the oxidative coupling thiols, oxidation of sulfides. Furthermore, the SA-DETA-Fe3O4 showed the high catalytic activity in Knoevenagel condensation of aromatic aldehydes with active methylene compounds (malononitrile and ethyl cynoacetate). The nanosolid catalyst could be easily recovered by a simple magnetic separation and reused for many cycles without deterioration in catalytic activity.Sulfamic acid immobilized on amino-functionalized magnetic Fe3O4 nanoperticles (SA-DETA-Fe3O4) was shown to be a versatile and highly efficient reusable catalyst for theorganic oxidation reactions and Knoevenagel condensation.
  PubDate: 2017-07-05T02:41:07.122614-05:
  DOI: 10.1002/aoc.3927
Structural designing, spectral and computational studies of bioactive
Schiff's base ligand and its transition metal complexes
- Authors: Seema Gautam; Sulekh Chandra, Hament Rajor, Swati Agrawal, Praveen Kumar Tomar
  Abstract: Transition metal complexes of Mn(II) and Ni(II) have been synthesized with novel bioactive Schiff's base ligand. Schiff's base ligand i.e. benzoylacetone-bis(2-amino-4-methylbenzothioazole) has been synthesized via condensation reaction between 2-amino-4-methylbenzothioazole and benzoylacetone in 2:1 ratio, respectively. Synthesized ligand has been characterized using elemental analysis, infra-red, 1H–NMR and mass spectroscopy techniques. Characterization of complexes was based on magnetic moment, molar conductance, elemental analysis, electronic spectra, infra-red and EPR spectroscopic techniques. Molar conductance data suggest that metal complexes are non-electrolytic in nature. Therefore, these complexes are formulated as [M(L)X2], where M = Mn(II), Ni(II), L = Schiff's base ligand, X = Cl−, CH3COO−, NO3−. Data of characterization study suggest octahedral geometry for Mn(II) and Ni(II) complexes. Geometry of metal complexes was also optimized with the help of computational study i.e. molecular modelling. Computational study also suggests octahedral geometry for complexes. Free ligand as well as its all metal complexes have been screened against the growth of pathogenic bacteria (E.coli, S.aureus) and fungi (C.albicans, C.krusei, C.parapsilosis, C.tropicalis) to assess their inhibition potential. The inhibition data revealed that metal complexes exhibit higher inhibition potential against the growth of bacteria and fungi microorganisms than free ligand.Synthesis and characterization of novel bioactive Schiff's base ligand and its metal complexes were done by various spectral techniques, molecular modelling.On the basis of characterization study data, metal complexes possess six coordinated octahedral geometry.Thermal data suggested that metal complexes are more thermal stable than free Schiff's base ligand.In vitro antibacterial and antifungal activity of synthesized ligand and its metal complexes were screened.All metal complexes were more biologically sensitive than ligand against the growth of microorganism.
  PubDate: 2017-07-05T02:35:37.330218-05:
  DOI: 10.1002/aoc.3915
A capable cobalt nano-catalyst for the N-formylation of various amines and
its biological activity studies
- Authors: Davood Habibi; Somayyeh Heydari, Mina Afsharfarnia
  Abstract: The Fe3O4 magnetic nanoparticles (Fe3O4 MNPs) were modified with 1,10-phenanthroline-5,6-diol and the relevant Co complex (Fe3O4@Phendiol@Co) synthesized as a nano-magnetic heterogeneous catalyst to be used for the N-formylation of various amines at room temperature under solvent-free conditions. Also, in order to find the better concept of the catalyst role, the N-formylation reaction was carried out by the use of ultrasound irradiation in the absence of the Co nano-catalyst and the results were compared. The catalyst characterized by different methods such as the elemental analysis (CHN), ICP, FT-IR, XRD, EDX, SEM, TEM, TG-DTA, VSM and XPS. In addition, the antioxidant and the antibacterial activities of the Fe3O4@Phendiol@Co nano-catalyst and its Phendiol ligand were in vitro screened by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and disc diffusion methods. Results showed that they possess strong antioxidant activity (IC50; 0.182 ± 0.006 mg/ml) and good antibacterial potential in comparison to standards.N-formylation of various amines by the Co nano-catalyst at room temperature under solvent-free conditions.
  PubDate: 2017-07-05T02:31:19.517165-05:
  DOI: 10.1002/aoc.3874
Synthesis, structure and in vitro antiproliferative activities of
oxamido-bridged dicopper(II) complexes: A comparative study of
experimental evidence and molecular docking of DNA/protein binding
- Authors: Ling-Yang Wang; Kang Zheng, Yan-Tuan Li, Zhi-Yong Wu, Cui-Wei Yan
  Abstract: Two μ-oxamido-bridged dicopper(II) complexes, namely [Cu2(hmpoxd)(H2O)(phen)](ClO4) (1) and [Cu2(papo)(H2O)(phen)](ClO4)·2H2O (2), where H3hmpoxd and H3papo represent N-(2-hydroxy-5-methylphenyl)-N′-[3-(dimethylamino)propyl]oxamide and N-(2-hydroxylphenyl)-N′-(3-aminopropyl)oxamide, respectively, and phen represents 1,10-phenanthroline, were synthesized. Single-crystal X-ray crystallography and other methods revealed that the two copper(II) ions in complex 1 are bridged by the cis-hmpoxd3− with Cu···Cu separation of 5.1896(7) Å, in which the inner (Cu1) and outer (Cu2) copper(II) atoms are located in square-planar and square-pyramidal geometries, respectively. To evaluate the effects of bridging ligand hydrophobicity on DNA/protein binding and potential anticancer activities, comparative studies of the reactivity towards herring sperm DNA and protein bovine serum albumin (BSA) as well as cytotoxicity of complex 1 with our previously reported complex 2 were conducted theoretically and experimentally. The results indicate that the two complexes can interact interactively with DNA, and bind to BSA via the binding sites Trp213 for 1 and Trp134 for 2. Interestingly, the in vitro anticancer activities and DNA/protein binding affinities consistently follow the order of 1> 2.The DNA/BSA binding properties of synthesized dicopper(II) complexes are studied theoretically and experimentally. The importance of bridging ligand hydrophobicity is highlighted.
  PubDate: 2017-07-05T02:25:54.914113-05:
  DOI: 10.1002/aoc.3940
Equisetum arvense As an abundant source of silica nanoparticles.
SiO2/H3PW12O40 nanohybrid material as an efficient and environmental
benign catalyst in the synthesis of 2-amino-4H-chromenes under
solvent-free conditions
- Authors: Reza Tayebee; Akbar Pejhan, Hassan Ramshini, Behrooz Maleki, Nasrin Erfaninia, Zohre Tabatabaie, Effat Esmaeili
  Abstract: Uniform SiO2 nanoparticles were successfully prepared from Equisetum arvense obtained from the north-east of Iran. Then, surface modification of the extracted nanoparticles was performed with a methanol solution of H3PW12O40 via wet impregnation method. The prepared nanocatalyst was characterized by XRD, FESEM, ICP, UV–Vis, and FT-IR spectroscopy. The supported heterogeneous nanocatalyst was successfully applied as a Lewis/Bronsted acid catalyst in the synthesis of a series of substituted 4H–chromenes via condensation of aromatic aldehydes, malononitrile, and 4-hydroxycoumarin under solventless conditions with fine yields in appropriately short times.SiO2/HPA nanoparticles were prepared, characterized and performed as efficient heterogeneous acid catalyst in the synthesis of substituted 4H–chromenes under solventless conditions.
  PubDate: 2017-07-05T02:20:51.035239-05:
  DOI: 10.1002/aoc.3924
Assembly immobilized palladium(0) on carboxymethylcellulose/Fe3O4 hybrid:
An efficient tailor-made magnetically catalyst for the Suzuki–Miyaura
couplings
- Authors: Zhuan Zhang; Yizong Zhang, Xiaoping Liu, Binbin Shen, Tianzhu Zhang, Yiqun Li
  Abstract: The Pd nanoparticles (Pd NPs) embedded on magnetically retrievable carboxymethylcellulose/Fe3O4 (Pd0@CMC/Fe3O4) organic/inorganic hybrid were prepared via the conventional simple process. The presence of the hydroxyl and carboxyl groups within the framework of the magnetic hybrid enables the facile preparation and stabilization of Pd NPs in this organic/inorganic hybrid. This hybrid catalyst was very effective in the Suzuki–Miyaura reaction of a variety of aryl halides with arylboronic acid to afford excellent product yields. The catalyst showed good stability and could be easily recovered with an external magnetic field and reused for several times without a significant loss in its catalytic activity. Furthermore, the Pd0@CMC/Fe3O4 hybrid catalyst was fully characterized by UV–Vis, FT–IR, XRD, SEM, EDX, TEM, XPS and TGA techniques. The hot filtration test suggests that a homogeneous mechanism is operative in Suzuki–Miyaura reaction.A novel magnetic organic/inorganic hybrid materials (CMC/Fe3O4) supported Pd nanoparticles (Pd0@CMC/Fe3O4) was prepared by a simple and low-cost approach without using any expensive organosilane. The as-synthesized Pd0@CMC/Fe3O4 hybrid exhibited excellent catalytic activities for Suzuki–Miyaura cross-coupling reactions in excellent yields.
  PubDate: 2017-07-05T02:16:10.720023-05:
  DOI: 10.1002/aoc.3912
Fe3O4-Methylene diphenyl diisocyanate-guanidine (Fe3O4–4,4′-MDI-Gn): A
novel superparamagnetic powerful basic and recyclable nanocatalyst as an
efficient heterogeneous catalyst for the Knoevenagel condensation and
tandem Knoevenagel-Michael-cyclocondensation reactions
- Authors: Razieh Maleki; Nadiya Koukabi, Eskandar Kolvari
  Abstract: In this paper, guanidine groups (Gn) supported on modified magnetic nanoparticles (Fe3O4–4,4′-MDI) were synthesized for the first time. The catalyst synthesized was characterized by various techniques such as SEM (Scanning Electron Microscopy), TEM (Transmission electron microscopy), XRD (X-ray Diffraction), TGA (Thermogravimetric ananlysis), EDS (Energy-dispersive X-ray spectroscopy) and VSM (vibrating sample magnetometer). The catalyst activity of modified MNPs–MDI-Gn, as powerful basic nanocatalyst, was probed through the Knoevenagel and Tandem Knoevenagel–Michael-cyclocondensation reactions. Conversion was high under optimal conditions, and reaction time was remarkably shortened. This nanocatalyst could simply be separated and recovered from the reaction mixture by simple magnetic decantation and reused many times without significant loss of its catalytic activity. Also, the nanocatalyst could be recycled for at least seven (Knoevenagel condensation) and six (Knoevenagel and Tandem Knoevenagel–Michael-cyclocondensation) additional cycles after they were separated by magnetic decantation and, washed with ethanol, air-dried, and immediately reused.In this paper, we successfully synthesized supported iron oxide magnetic nanoparticles (Fe3O4–4,4′-MDI-Gn) from readily available starting materials. It was applied as magnetically recyclable and powerful basic heterogeneous nanocatalyst for the Knoevenagel and Tandem Knoevenagel–Michael-cyclocondensation reactions in excellent yields and short reaction times. This nanocatalyst could simply be separated and recovered from the reaction mixture by simple magnetic decantation and reused many times without significant loss of its catalytic activity. Furthermore, the catalyst could be recovered and reused without significant degradation in activity.
  PubDate: 2017-07-05T02:10:40.748112-05:
  DOI: 10.1002/aoc.3905
Electronic structures and photophysical properties of phosphorescent
platinum (II) complexes with tridentate C^N*N cyclometalated ligands
- Authors: Wenqian Li; Jian Wang, Xi Yan, Huize Zhang, Wei Shen
  Abstract: To get an insight into the structure–property relationships in a series of strongly phosphorescent platinum(II) complexes with tridentate C^N*N cyclometalated ligands, their electronic structures and electroluminescence properties were systematically investigated via density functional theory and time-dependent density functional theory. Moreover, the factors related to the radiative and non-radiative decay process, including the transition electric dipole moment μ(Sn), the energy difference between singlet and lowest triplet excited states ΔE(Sn–T1) and the spin–orbital coupling matrix elements ⟨Sn ĤSOC T1⟩, as well as the energy gap between T1 and S0 states ΔE(T1–S0) and absorption–emission Stokes shifts have been calculated. Fine emission color tuning and high phosphorescence quantum yield of phosphorescent complexes may be achieved through introducing five–six-membered metallacycle geometries and linking a substituent (such as phenyl) at bridge atoms. Additionally, phosphorescent properties of these complexes show a clear dependence on the electronegativity of bridge atoms.Heteroatoms were incorporated into the bridges between two pyridyls in main ligands to study the structure–property relationships of cyclometalated Pt(II) complexes and inspire new ideas for designing tridentate Pt(II) complexes.
  PubDate: 2017-06-29T02:35:46.603326-05:
  DOI: 10.1002/aoc.3929
Novel CuFe2O4@SiO2-OP2O5H magnetic nanoparticles: Preparation,
characterization and first catalytic application to the synthesis of
1,8-dioxo-octahydroxanthenes
- Authors: Farzaneh Tajfirooz; Abolghasem Davoodnia, Mehdi Pordel, Mahmoud Ebrahimi, Amir Khojastehnezhad
  Abstract: New functionalized magnetic core–shell nanoparticles, CuFe2O4@SiO2-OP2O5H, were prepared by grafting of phosphorus pentoxide on CuFe2O4@SiO2 nanoparticles and characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis, inductively coupled plasma optical emission spectrometry and vibrating sample magnetometry. The catalytic activity of CuFe2O4@SiO2-OP2O5H as a novel catalyst was evaluated in the synthesis of 1,8-dioxo-octahydroxanthenes under solvent-free conditions. The results showed that the catalyst has high activity and the desired products are obtained in high yields within short reaction times. The catalyst is readily recovered using magnetic decantation and can be used at least four times without noticeable deterioration in catalytic activity.New functionalized magnetic core–shell nanoparticles, CuFe2O4@SiO2-OP2O5H, were prepared by grafting of phosphorus pentoxide on CuFe2O4@SiO2 nanoparticles and characterized. The catalytic activity of CuFe2O4@SiO2-OP2O5H was evaluated in the synthesis of 1,8-dioxo-octahydroxanthenes under solvent-free conditions. The catalyst has high activity leading to products in high yields within short reaction times. The catalyst is readily recovered by magnetic decantation and can be used at least four times without loss of catalytic activity.
  PubDate: 2017-06-29T02:30:54.554761-05:
  DOI: 10.1002/aoc.3930
Tri- and diorganotin(IV) derivatives of non-steroidal anti-inflammatory
drug sulindac: Characterization, electronic structures (DFT), DNA binding
and plasmid cleavage studies
- Authors: Ranjana Kumari; Mala Nath
  Abstract: Tri- and diorganotin(IV) derivatives of non-steroidal anti-inflammatory drug sulindac (Sul), coordinated with carboxylate oxygen, namely C23H25FO3SSn (1), C38H31FO3SSn (2), C32H43FO3SSn (3), C52H42F2O6S2Sn (4), C44H44S2Cl2O6F2Sn2 (5), C48H50F2O6S2Sn (6) and C56H66F2O6S2Sn (7), have been synthesized and characterized using analytical and spectroscopic (IR, 1H NMR, 13C NMR, 119Sn NMR and ESI-MS) techniques. Optimized geometry and electronic structures of the complexes obtained from density functional theory calculations indicate that complexes 1, 2, 3 and 7 are tetra-coordinated with monodentate carboxylates, 4 and 6 are hexa-coordinated with highly distorted octahedral geometry, whereas 5 is penta-coordinated with distorted trigonal bipyramidal geometry. Probable mode of DNA binding with ligand (Sul) and complexes 1–7 has been revealed via various biophysical techniques (UV–visible spectroscopy, fluorometry and circular dichroism). Intrinsic binding constants (Kb) obtained from UV–visible spectroscopy for Sul and complexes 1–7 are 3.69 × 104, and 7.3 × 103, 1.14 × 104, 1.47 × 104, 1.55 × 104, 1.49 × 104, 2.02 × 104, 1.17 × 104 M−1, respectively. The quenching constants (Ksv) using fluorometric titrations, calculated from competitive binding of ethidium bromide versus Sul/complexes with calf thymus DNA, also correspond to the above results. Circular dichroism spectral patterns of calf thymus DNA with Sul and complexes 1–7 have also been investigated. All the results reveal that the complexes bind with DNA through partial intercalative mode. pBr322 plasmid fragmentation has also been studied using gel electrophoresis, which shows the fragmentation of circular DNA by an increase in nicked form and also by the appearance of linear form with increasing concentration of drug or complexes.Organotin(IV) derivatives of NSAID, Sulindac have been synthesized, and their interaction with DNA studied through UV-visible, fluorescence and circular-dichroism spectroscopy revealed the partial intercalation mode of binding. Plasmid DNA cleavage study indicates the formation of nicked and linear form.
  PubDate: 2017-01-11T22:30:50.528337-05:
  DOI: 10.1002/aoc.3661
Palladium nanoparticles decorated on reduced graphene oxide: An efficient
catalyst for ligand- and copper-free Sonogashira reaction at room
temperature
- Authors: Abhijit Mahanta; Najrul Hussain, Manash R. Das, Ashim J. Thakur, Utpal Bora
  Abstract: This article focuses on a room temperature copper-free Sonagashira cross-coupling reaction in ethanol, catalysed by palladium nanoparticles homogeneously deposited on reduced graphene oxide. The catalyst showed efficient catalytic activity towards the said coupling reaction, and was well characterized using various techniques, and could be reused up to six times with almost constant yield of the desired product. The attractions of this protocol are that the reaction completes within short reaction time under ligand- and copper-free conditions and it avoids harsh reaction conditions.An in situ synthesis of Pd nanoparticles decorated on reduced graphene oxide has been developed, which was used as an excellent catalyst for Sonogashira coupling reaction at room temperature under copper-, ligand- and amine-free conditions.
  PubDate: 2017-01-11T21:15:27.48549-05:0
  DOI: 10.1002/aoc.3679