Enantiomerically enriched (R)- and (S)-alpha-methylphenylalanine via asymmetric PTC C-alkylation catalysed by NOBIN

Abstract

Enantiopure 2-hydroxy-2'-amino-1,1'-binaphthyl (NOBIN) is shown to catalyse C-alkylation of aldimine Schiff's bases of alanine ester under phase-transfer catalysis conditions (solid NaOH or NaH, toluene, ambient temperature, 10% NOBIN).