Chitosan Supported Chiral Heterogenous Catalyst and Application in Transfer Hydrogenation of Acetophenone

摘要

Over the past three decades, homogenous asymmetric catalysis was subjected to a successful development. But only a few examples have been develop to an industrial scale. The lack of employment of the homogenous asymmetric catalysis is probably and essentially due to problems of separation and recycling of the expensive chiral catalyst. In order to meet the increasing ecological and economic regulations for the development of chemical process, more attention is being paid to the use of heterogenous catalysis. A chiral heterogenous catalyst was prepared with chitosan and silica, and then PdCl_2 · H_2O was supported on it under reflux in ethanol. The hydrogenation of acetophenone was conducted with hydride transfer reduction, after reaction, the catalyst was recovered and the reduction productions were identify and measured directly. The production is identified by GC-MS, Conversion and optical yield were determined by gas chromatograph with a chiral capillary column.