Enantioselective Hydrogenation of (<i>E</i>)-α-Phenylcinnamic Acid over Cinchonidine-Modified Palladium Catalysts

Abstract

Abstract Prochiral (E)-α-phenylcinnamic acid was hydrogenated enantioselectively over alumina- and titania-supported Pd catalysts modified with cinchonidine giving optical yields of 36.9% and 44.4%, respectively, in favor of (S)-(+)-2,3-diphenylpropionic acid. The influence of solvent on the optical yield was significant; a water containing solvent gave the best result.