Enantioselective hydrogenation of ethyl 2-oxo-4-phenylbutyrate to ethyl (R)-2-hydroxy-4-phenyl- bu- tyrate on Pt/γ-Al2O3 modified by 10,11-dihydrocinchonidine was studied by investigating the influences of the amou...Enantioselective hydrogenation of ethyl 2-oxo-4-phenylbutyrate to ethyl (R)-2-hydroxy-4-phenyl- bu- tyrate on Pt/γ-Al2O3 modified by 10,11-dihydrocinchonidine was studied by investigating the influences of the amount of modifier, initial concentration of reactant, pressure and temperature on conversion and enantiometric excess in a stirred autoclave and the effects of the liquid velocity, gas velocity, modifier concentration and various catalytic beds in a trickle-bed reactor. The maximum optical yields were about 50% and 60% in the two types of reactors, respectively. It was assumed that the total hydrogenation rate included the reaction rates over the unmodified and modified active sites on platinum surface and a kinetic model, which fitted the experimental data well in autoclave, was obtained. A simplified plug-flow model was proposed to describe the bed average efficiency of trickle-bed reactor.展开更多
The crystal structure of the title compound C16H18NO2+·C7H7SO3-·2H2O, (C23H29NSO7, Mr=463.53) has been determined by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system wi...The crystal structure of the title compound C16H18NO2+·C7H7SO3-·2H2O, (C23H29NSO7, Mr=463.53) has been determined by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system with space group P21/n, a=8.101(1), b=8.958(2), c=33.281(5)?,β= 94.910(1)(, V=2406.3(7)?3, Z=4, Dc=1.279g/cm3, μ=0.176mm-1, F(000)=984, final R=0.0409, and Rw=0.0860 for 4401 independent reflections. The result shows that in the crystal structure of the title compound the planar cations have two configurations with equal occupation ratio and are antiparally packed through π…π interactions. Similar packing energies in A and B are probably the main factor that leads to the disorder structure.展开更多
文摘Enantioselective hydrogenation of ethyl 2-oxo-4-phenylbutyrate to ethyl (R)-2-hydroxy-4-phenyl- bu- tyrate on Pt/γ-Al2O3 modified by 10,11-dihydrocinchonidine was studied by investigating the influences of the amount of modifier, initial concentration of reactant, pressure and temperature on conversion and enantiometric excess in a stirred autoclave and the effects of the liquid velocity, gas velocity, modifier concentration and various catalytic beds in a trickle-bed reactor. The maximum optical yields were about 50% and 60% in the two types of reactors, respectively. It was assumed that the total hydrogenation rate included the reaction rates over the unmodified and modified active sites on platinum surface and a kinetic model, which fitted the experimental data well in autoclave, was obtained. A simplified plug-flow model was proposed to describe the bed average efficiency of trickle-bed reactor.
文摘The crystal structure of the title compound C16H18NO2+·C7H7SO3-·2H2O, (C23H29NSO7, Mr=463.53) has been determined by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system with space group P21/n, a=8.101(1), b=8.958(2), c=33.281(5)?,β= 94.910(1)(, V=2406.3(7)?3, Z=4, Dc=1.279g/cm3, μ=0.176mm-1, F(000)=984, final R=0.0409, and Rw=0.0860 for 4401 independent reflections. The result shows that in the crystal structure of the title compound the planar cations have two configurations with equal occupation ratio and are antiparally packed through π…π interactions. Similar packing energies in A and B are probably the main factor that leads to the disorder structure.
基金Supported by the National Natural Science Foundation of China (Grant No. 20972112)the Key Project Foundation of the Science and Technoloev Ministry of People's Republic of China (Grant No. 2007BAI41B01)~~