Catalytic activity of manganese oxide supported on alumina in the synthesis of quinoxalines  

作　　者：Rekha M. Kathyayini H Nagaraju N 

机构地区：[1]Catalysis Research Laboratory, St Joseph's College Post Graduate and Research Centre, Bangalore 560027, India [2]Centre for Emerging Technologies, Global Campus Jain University, Bangalore 562112, India

出　　处：《Frontiers of Chemical Science and Engineering》2013年第4期415-421,共7页化学科学与工程前沿（英文版）

摘　　要：Two catalysts, alumina and manganese oxide supported on alumina, have been prepared by calcination and precipitation-impregnation methods, respectively. The catalysts are characterised by the following techniques： Brunner-Emmett-Teller-N2 adsorption-desorption for sur- face area, temperature programmed desorption of NH3 and n-butyl amine back titration methods for surface acidity, powder X-ray diffraction for textural properties, and Fourier transform infrared spectroscopy for the anionic radicals. The catalytic activity has been determined under heterogeneous conditions in the condensation reaction between o-phenylenediamine and benzil. The product purity is checked by thin-layer chromatography and melting point. The products are also analysed by LC-MS and 1H-NMR techniques. The yields of the products have been found to be good and catalysts exhibited excellent recyclability. The effect of changing the reaction para- meters such as temperature, reaction time, amount of the catalyst, nature of solvent and molar ratio of reactants on the yield of the product has been studied. The surface acidity of the catalysts plays an important role in activating the reaction.Two catalysts, alumina and manganese oxide supported on alumina, have been prepared by calcination and precipitation-impregnation methods, respectively. The catalysts are characterised by the following techniques： Brunner-Emmett-Teller-N2 adsorption-desorption for sur- face area, temperature programmed desorption of NH3 and n-butyl amine back titration methods for surface acidity, powder X-ray diffraction for textural properties, and Fourier transform infrared spectroscopy for the anionic radicals. The catalytic activity has been determined under heterogeneous conditions in the condensation reaction between o-phenylenediamine and benzil. The product purity is checked by thin-layer chromatography and melting point. The products are also analysed by LC-MS and 1H-NMR techniques. The yields of the products have been found to be good and catalysts exhibited excellent recyclability. The effect of changing the reaction para- meters such as temperature, reaction time, amount of the catalyst, nature of solvent and molar ratio of reactants on the yield of the product has been studied. The surface acidity of the catalysts plays an important role in activating the reaction.

关 键 词：ALUMINA manganese oxide deposited onalumina quinoxaline synthesis 

分 类 号：O643.36[理学—物理化学] TQ133.1[理学—化学]