Substituent-Dependent Asymmetric Synthesis of L-threo- and L-erythro-( 2,3-2H2)Phenylalanine from Chiral (Z)-Dehydrophenylalanine.

A stereo-divergent synthesis of L-threo- and L-erythro-[2,3-2H2]-phenylalanine by a catalytic deuteriation of (Z)-dehydrophenylalanine included in a chiral diketopiperazine ring is accomplished simply by changing the substituents on the nitrogen atoms in the diketopiperazine ring.