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

Highly enantioselective synthesis of a potent metabotropic receptor ligand, (2S)-α-(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 CH2Cl2 at −60 °C in the presence of (S)-binaphthyl quaternary ammonium salt 4.