Highly Efficient Synthesis of β-Amino Acid Derivatives via Asymmetric Hydrogenation of Unprotected Enamines

Abstract

A direct asymmetric hydrogenation of unprotected enamino esters and amides is described. Catalyzed by Rh complexes with Josiphos-type chiral ligands, this method gives beta-amino esters and amides in high yield and high ee (93-97% ee). No acyl protection/deprotection is required.