The Experts below are selected from a list of 237 Experts worldwide ranked by ideXlab platform
Bahador Karami - One of the best experts on this subject based on the ideXlab platform.
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Molybdic Acid-Functionalized Nano-Fe3O4@TiO2 as a Novel and Magnetically Separable Catalyst for the Synthesis of Coumarin-Containing Sulfonamide Derivatives.
Acta chimica Slovenica, 2020Co-Authors: Jamileh Etemad Gholtash, Bahador Karami, Mahnaz Farahi, Mahsa AbdollahiAbstract:Supported Molybdic Acid on nano-Fe 3 O 4 @TiO 2 (Fe 3 O 4 @TiO 2 @(CH 2 ) 3 OMoO 3 H) has been successfully prepared, characterized and applied as a catalyst for the synthesis of sulfonamide containing coumarin moieties. The prepared Fe 3 O 4 nanoparticles by coprecipitation of Fe 2+ and Fe 3+ ions were treated with tetraethyl orthotitanate to obtain Fe 3 O 4 @TiO 2 . By anchoring 3-chloropropyltriethoxysilan on Fe 3 O 4 @TiO 2 followed by reacting with Molybdic Acid, the desired catalyst was produced. The synthesized catalyst was characterized using XRD, SEM, EDS, FT-IR and VSM analysis. Fe 3 O 4 @TiO 2 @(CH 2 ) 3 OMoO 3 H was used as a catalyst for the synthesis of sulfonamide containing coumarin moieties via a three-component reaction of aryl aldehydes, para -toluenesulfonamide and 4-hydroxycoumarin or 5,7-dihydroxy-4-methylcoumarin. The catalyst recovery test showed the catalyst is highly reusable without losing its activity.
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Molybdic Acid functionalized nano fe3o4 tio2 as a novel and magnetically separable catalyst for the synthesis of coumarin containing sulfonamide derivatives
Acta Chimica Slovenica, 2020Co-Authors: Jamileh Etemad Gholtash, Bahador Karami, Mahnaz Farahi, Mahsa AbdollahiAbstract:Supported Molybdic Acid on nano-Fe 3 O 4 @TiO 2 (Fe 3 O 4 @TiO 2 @(CH 2 ) 3 OMoO 3 H) has been successfully prepared, characterized and applied as a catalyst for the synthesis of sulfonamide containing coumarin moieties. The prepared Fe 3 O 4 nanoparticles by coprecipitation of Fe 2+ and Fe 3+ ions were treated with tetraethyl orthotitanate to obtain Fe 3 O 4 @TiO 2 . By anchoring 3-chloropropyltriethoxysilan on Fe 3 O 4 @TiO 2 followed by reacting with Molybdic Acid, the desired catalyst was produced. The synthesized catalyst was characterized using XRD, SEM, EDS, FT-IR and VSM analysis. Fe 3 O 4 @TiO 2 @(CH 2 ) 3 OMoO 3 H was used as a catalyst for the synthesis of sulfonamide containing coumarin moieties via a three-component reaction of aryl aldehydes, para -toluenesulfonamide and 4-hydroxycoumarin or 5,7-dihydroxy-4-methylcoumarin. The catalyst recovery test showed the catalyst is highly reusable without losing its activity.
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Synthesis and characterization of Molybdic Acid immobilized on modified magnetic nanoparticles as a new and recyclable catalyst for the synthesis of chromeno[4,3-b]chromenes
New Journal of Chemistry, 2017Co-Authors: Foroogh Khosravian, Bahador Karami, Mahnaz FarahiAbstract:As the basic task of the current study, Molybdic Acid immobilized on 3-chloropropyl-grafted magnetic silica-coated Fe3O4 nanoparticles (Fe3O4@SiO2@(CH2)3OMoO3H), as a recyclable catalyst, was synthesized and characterized via FT-IR, X-ray diffraction pattern (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and vibrating sample magnetometer (VSM) analysis. The catalytic performance of this novel nanocatalyst was evaluated for the preparation of a wide range of chromeno[3,4-b]chromene derivatives in excellent yields. It is a low-cost, nontoxic, and recoverable catalyst that provides environmentally friendly reaction conditions. Additionally, the reaction does not require very high temperatures. The catalyst can be reused many times without a significant loss of its activity.
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Nanosilica Molybdic Acid: synthesis, characterization and application as a green and reusable catalyst for the Pechmann condensation
Journal of the Iranian Chemical Society, 2016Co-Authors: Mahtab Kiani, Bahador KaramiAbstract:Nanosilica Molybdic Acid (SMA NPs) was founded as an efficient and recyclable nanocatalyst for the synthesis of coumarin derivatives in excellent yields with good purity. Nano-SMA as a new solid Acid was characterized by X-ray fluorescence, X-ray diffraction, energy-dispersive X-ray analyzer, transmission electron microscopy and Fourier transform infrared spectroscopy. Coumarin derivatives were obtained via the Pechmann condensation reaction of phenols and β-ketoesters at 80 °C under solvent-free conditions. The main advantages of the present procedure are high yields, shorter reaction time and green chemistry procedure, simple work-up and inexpensive and reusability of the catalyst.
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Silica-Supported Molybdic Acid: Preparation, Characterization, and Its Catalytic Application in Synthesis of Pyranocoumarins.
ChemInform, 2016Co-Authors: Bahador Karami, Mahtab KianiAbstract:Silica-supported Molybdic Acid was employed as novel, recyclable, and safe catalyst in a one-pot three- component condensation of aldehydes, malononitrile, and 4-hydroxycoumarin to produce new and known pyr- ano(2,3-c)chromenes as potent biologically active compounds. This expedient new route has advantages, such as the use of a safe and reusable catalyst, simple operation, short reaction times, and good to excellent yields. The silica-supported Molybdic Acid as a novel solid Acid was characterized by X-ray fluorescence, X-ray diffraction, and Fourier transform infrared spectroscopy. Graphical abstract
Jian Gong - One of the best experts on this subject based on the ideXlab platform.
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Chemical Syntheses of the Conducting Material Formed by HeteropolyAcids and Polyaniline
Polymer Journal, 2001Co-Authors: Jian Gong, Rui-nian Hua, Zhong-wei Xie, Shou-guo WangAbstract:Here we report a hybrid organic-inorganic conducting material formed by vanadium-containing silicotungstic/Molybdic or phosphotungstic/Molybdic Acid and polyaniline (PAN) with a one-step or a two-step chemical reaction involving oxidation of aniline with ammonium persulfate in the presence of vanadium-containing silicotungstic/Molybdic or phosphotungstic/Molybdic Acid. Polymer structure was examined by elemental analysis, IR, XRD, XPS, and thermal stability and conducting behavior was studied. Results showed that the composition and structure of main chain with one-step method were similar to that with two-step method. However, some differences in XRD spectra between the polymer with one-step and two-step methods were observed, which may be due to differences of doping methods. Conductivity of materials with a one-step method was bigger than that with a two-step method when the percentage of doping was determined. When heteropolyAcid as doping agent was determinate, conductivity increased with doping percentage at the beginning and rate of conductivity was faster in the two-step method than in the one-step method. However conductivity did not increase with doping percentage when the doping percentage increased to a certain range. The conductivity of the materials descended after the materials were heated. One reason was dedoping or degradation of the materials.
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H4PM11VO40-doped (M=W,Mo) polyaniline-synthesis, characterization and catalytic conversion of isopropanol
Synthetic Metals, 1999Co-Authors: Jian Gong, R.s. WangAbstract:New type polymer as catalysts for isopropanol conversion were prepared from polyaniline and vanadium-containing phosphotungstic/Molybdic Acid. The polymers were characterized by elemental analysis, IR, XPS, TG, and the conductivity were determined. The catalysis activity of doped polyaniline were studied.
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Syntheses, characterization and conductivity of polyaniline doped with H5SiM11VO40(M=Mo,W)
Synthetic Metals, 1999Co-Authors: Jian Gong, Z.-m. Dai, Rongshun WangAbstract:Abstract Polyaniline (PANI) doped with vanadium-containing silicotungstic/Molybdic Acid have been prepared in a one-step chemical reaction. The polymers were characterised by elemental analysis, IR, XRD, The thermal stability and the conductive property of doped PANI were determined,
Wang Yue-li - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of iso-amyl acetate catalyzed by worm-like molecular sieve supported phospho-tungstic-Molybdic Acid
Journal of Molecular Science, 2014Co-Authors: Wang Yue-liAbstract:The supported phospho-tungstic-Molybdic Acid catalysts were prepared by loading phosphotungstic-Molybdic Acid on the Worm-like mesporous carrier via the impregnation method.The catalysts were characterized by XRD,FT-IR and N2adsorption-desorption.The iso-amyl acetate was synthesized by supported phospho-tungstic-Molybdic Acid as the catalyst.The effects of reaction parameters such as n(acetic Acid)∶n(iso-amyl alcohol),reaction time,the dosage of cyclohexane and supported catalyst,loading amounts of phospho-tungstic-Molybdic Acid on the esterification rate and the reuse performance of supported catalyst were studied.The results showed that esterification rate was up to 92.8% when the supported phospho-tungstic-Molybdic Acid catalyst was used under the optimal conditions.In addition,the supported catalyst has good reproductively.
Rongshun Wang - One of the best experts on this subject based on the ideXlab platform.
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Syntheses, characterization and conductivity of polyaniline doped with H5SiM11VO40(M=Mo,W)
Synthetic Metals, 1999Co-Authors: Jian Gong, Z.-m. Dai, Rongshun WangAbstract:Abstract Polyaniline (PANI) doped with vanadium-containing silicotungstic/Molybdic Acid have been prepared in a one-step chemical reaction. The polymers were characterised by elemental analysis, IR, XRD, The thermal stability and the conductive property of doped PANI were determined,
Manuel Martinez-maldonado - One of the best experts on this subject based on the ideXlab platform.
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A simple spectrophotometric determination of submicromolar quantities of vanadium oxyions
Journal of pharmaceutical and biomedical analysis, 1994Co-Authors: C. Rodriguez, Estela S. Estapé-wainwright, M.b. Sidhom, José L. Cangiano, Manuel Martinez-maldonadoAbstract:Widespread interest has developed in the study of vanadium as an essential nutrient [l] and as a possible regulator of several ATP hydrolysing enzymes [2-41 in mammalian species. Available methods for the determination of vanadium are costly [l, 5, 61, complex [7-121, and of very low sensitivity [13, 141. Oxyvanadium species are known to react with Molybdic Acid in the presence of phosphate to form a heteropolymolybdate complex [ 15, 161. The complex, molybdivanadophosphoric Acid, is characterized by a yellow colour that maximally absorbs light at 385 nm. The intensity of colour resulting from the formation of this heteropoly complex has been shown to vary with changes in the concentration of inorganic phosphate. The dependence of the reaction on the concentration of vanadium oxyions has not been evaluated. In the present study we examined the possibility that the intensity of yellow colour development resulting from the reaction of oxyvanadium with Molybdic Acid and phosphate may vary as a function of oxyvanadium concentration. The effect of phosphate ions and the pH of the medium on the colour intensity were also investigated. The study included the stoichiometric determination of the composition of the complex species. Experimental