Highly Enantioselective Synthesis of (2S)-α-(Hydroxymethyl)-glutamic Acid by the Catalytic Michael Addition of 2-Naphthalen-1-yl-2-oxazoline-4-carboxylic Acid tert-Butyl Ester

[reaction: see text]. Highly enantioselective synthesis of a potent metabotropic receptor ligand, (2S)-alpha-(hydroxymethyl)-glutamic acid (2, HMG) was accomplished by the catalytic Michael addition of 2-naphthalen-1-yl-2-oxazoline-4-carboxylic acid tert-butyl ester (3b), using the phosphazene base, BEMP, in CH(2)Cl(2) at -60 degrees C in the presence of (S)-binaphthyl quaternary ammonium salt 4.