THE DETERMINATION OF CHIRALITY OF N-METHYL-PHENYLALANINE AND N,N-DIMETHYL-PHENYLALANINE BY GLC

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.