Chiral 1,3-oxazolidines as the ligands for the enantioselective addition of diethylzinc to aryl aldehydes

Various 1,3-oxazolidines have been prepared from norephedrine and aldehydes/ketones and the corresponding zinc amides prepared in situ have been utilized as catalysts for the enantioslective addition of diethylzinc to aryl aldehydes. Good enantioselectivities (73-85%) and consistent product configuration are realized in all the cases examined. A mechanism has been proposed that can account for the stereochemical outcome.