New beta-amino alcohols as chiral ligands for the catalytic enantioselective reduction of prochiral ketones and the nucleophilic addition of diethylzinc to benzaldehyde

New optically active beta-amino alcohols, derived from various acyclic and cyclic amino acids with alkyl groups on the carbinol carbon atom, were used in the enantioselective reduction of prochiral ketones. The attachment of alkyl groups to the nitrogen atom of the catalyst (R)-1b was shown to influence favorably the enantioselectivity of the addition of diethylzinc to benzaldehyde. In both cases the resulting secondary alcohols were obtained in moderate to high optical yields.