Method for the Racemization of Optically Active Amino Acids

Article abstract of DOI:10.1021/jo00154a019

A practical method for the racemization of optically active amino acids has been developed.A wide variety of optically active α-amino acids, including neutral amino acids, acidic amino acids, basic amino acids, and imino acids, could be racemized by heating in a medium of acetic acid at 80-100 deg C for 1 h in the presence of 0.05 molar equiv of an aliphatic or an aromatic aldehyde.The factors influencing the racemization were investigated.Phenylglycine, (p-hydroxyphenyl)glycine, and serine could be racemized without complete dissolution of the optically active isomers.Thus, isolation of the racemic modification was easily achieved by simple filtration of the racemic modification suspended in the reaction mixture.The mechanism of the racemization is discussed.