First synthesis of the two enantiomers of α‐methyldiphenylalanine [(αMe)Dip] by HPLC resolution

Resumen

Abstract A strategy for the preparation of enantiomerically pure (R)‐ and (S)‐α‐methyldiphenylalanine, constrained phenylalanine analogs, is described. A racemic precursor was prepared in high yield from easily available starting products and subjected to HPLC resolution on a noncommercial chiral stationary phase. More than 600 mg of each enantiomer was isolated in optically pure form by using a 150 × 20 mm ID column containing mixed 10‐undecenoate/3,5‐dimethylphenylcarbamate of cellulose covalently bonded to allylsilica gel and a mixture of n ‐hexane/2‐propanol/acetone as the mobile phase. Chirality 14:39–46, 2002. © 2002 Wiley‐Liss, Inc.