Asymmetric Reduction of Aromatic Ketones Catalyzed by Using (αs,4s)-2-Dichloromethyl-4, 5-Dihydro-α- (4-Nitrophenyl)-4- Oxazolemethanol-Borane Complex

Chiral oxazoborolidine borane complex was prepared from (αs,4s)-2-dichloromethyl-4,5-dihy-dro-α-(4-nitrophenyl)-4-oxazolemethanol with Borane in THF. The borane modified by chiral oxazoboro-lidine enantioselectively reduced aromatic ketones to second-alcohol with about 95% yield and medium op-tical yields. In the end of article, results are discussed and reduction mechanism is shown which proves theresulting major isomers fit very well.