An Efficient Asymmetric Synthesis of (3S)-3-Amino-1-(4-cyanophenyl)-2-oxopyrrolidine Hydrochloride Salt.

Abstract Reaction of 4-aminobenzonitrile with 2-bromo-4-chlorobutyryl bromide in the presence of sodium phosphate followed by treatment of the coupled product with sodium hydroxide followed by ammonium hydroxide in acetonitrile yielded the title compound as the racemic ( R )-(−)-mandelic acid salt in an overall yield of 64%. The title compound was then obtained with an ee >96% and in 78% yield after a dynamic resolution of the racemic salt in IPA using a catalytic amount of salicylaldehyde followed by salt exchange.