Enantioselective addition of Et2Zn to aldehydes catalyzed by chiral aliphatic β-amino alcohols

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