The Determination of Chirality of N-Methyl- and N,N-Dimethyl-phenylalanine by G.L.C.

Abstract

The chirality of N- methylphenylalanine enantiomers can be determined on a micro scale by g.l.c . of N-pentafluoropropionyl amino acid isopropyl esters on a Chirasil -L-Val capillary column. N,N- Dimethylphenylalanine enantiomers cannot be similarly derivatized and cannot be separated. However, prior treatment with ethyl chloroformate followed by acid hydrolysis effects demethylation to the N-methyl analogues which can then be derivatized for g.l.c . Contrary to literature reports N-methylphenylalanine can be prepared by reductive alkylation of phenylalanine.