Optical Resolution and Asymmetric Transformation of (RS)-N-Alkyl- and (RS)-N,N-Dialkyl-2-phenylglycines

Article abstract of DOI:10.1246/bcsj.66.1430

Optical resolution of (RS)-N-methyl-2-phenylglycine <(RS)-Mpg> and (RS)-N-ethyl-2-phenylglycine <(RS)-Epg> was carried out by using (1S)-10-camphorsulfonic acid <(S)-CS> as resolving agents, and that of (RS)-N-ethyl-N-methyl-2-phenylglycine <(RS)-Emp> by (R)- and (S)-1-phenylethylamine.Racemization rates of optically active Mpg, Epg, Emp, N,N-dimethyl-2-phenylglycine , and six α-amino acids were measured by heating in carboxylic acids.The electron-donating amino acid side chain and N-substituted alkyl group decreased therate to inhibit the formation of intermediary carbanions, whereas the electron-withdrawing side chain increased it.Asymmetric transformation of (RS)-Mpg, (RS)-Epg, and (RS)-Dmp was carried out on the basis of the results of optical resolution and racemization to give the corresponding enantiomers of approximately 100percent optical purities in over 70percent yield based on the sterting racemates.