This paper describes the preparation of two new optically active aliphatic β-amino alcohols (R)-5,5-dimethyl-2-(dimethy-lamino)-1,1-diphenyl-1-hexanol (1a) and (S)-8,8-dimethyl-2-(dimethylamino)-1, 1-diphenyl-1-nonanol (1b). They were synthesized by methylation of the corresponding β-amino alcohols 2a and 2b. Compounds la and 1b catalyze the addition of diethylzinc to various aldehydes enantioselectively. The catalyst structure-enantioselectivity relationships were discussed. This paper describes the preparation of two new optically active active β-amino alcohols (R) -5,5-dimethyl-2- (dimethy lamino) -1,1-diphenyl- They were synthesized by methylation of the corresponding β-amino alcohols 2a and 2b. Compounds 1a and 1b catalyzed the addition of diethylzinc to various aldehydes enantioselectively. The catalyst structure-enantioselectivity relationships were discussed.