Chiral Schiff bases as highly active and enantioselective catalysts in catalytic addition of dialkylzinc to aldehydes.

We have developed chiral Schiff base catalysts based on the ONO-tridentate ligand for the catalytic enantioselective addition of dialkylzinc to aldehydes. Various aldehydes were smoothly converted into corresponding optically active secondary alcohols with high enantioselectivity (up to 98 % ee) in high yield. Furthermore, we have succeeded in decreasing the catalyst loading minimum to 0.1 mol % in the chiral Schiff base-catalyzed enantioselective alkylation of aldehydes.