Supported ruthenium catalyst

complexes of TsDPEN supported with mesoporous silica microspheres of various morphologies and structures

which were synthesized by a simple one-step in situ polymerization- induced precipitation procedure

were prepared for the asymmetric transfer hydrogenation of acetophenone. The mesoporous structure of silica microspheres were observed by the nitrogen adsorption/desorption isotherms and field emission scanning electron microscopy (FESEM)

ruthenium complex well distributed on silica microspheres by transmission electrum microscopy (TEM)

and the existence of hydrogen bonds between catalyst and regents by infrared spectrometry (IR). Effect of support structure and reaction conditions such as reaction temperature and time

and reactant concentration on catalytic performances for the asymmetric transfer hydrogenation of acetophenone were investigated. It showed that the interaction between ruthenium complexes with supports of small pore size and high specific surface area promoted the asymmetric transfer hydrogenation and channel stereo-confinement of mesoporous silica microspheres

resulting in significant enhancement of the activity and optical selectivity of the reaction. Under the optimum of 40℃

16 h and 0.2 ml acetophenone of reaction conditions

the catalyst achieved its highest 64.1% and 93.4% of acetophenone conversion and enantio selectivity of R-α-phenethyl alcohol for asymmetric transfer hydrogenation of acetophenone

respectively.