Process for the racemization of α-amino acids

According to the present invention, a method is provided wherein a basic aqueous phase containing an optically active α-amino acid is brought into contact with an organic phase containing a racemisation catalyst in the form of a copper metal complex of copper ions and an α-amino acid and salicylaldehyde, in the presence of a phase transition catalyst, thereby subjecting the optically active α-amino acid to racemisation. In the α-amino acid racemisation method according to the present invention, the reaction conditions are mild and thus there is little α-amino acid breakdown and the yield is high, the racemisation catalyst can be reused, the α-amino acid resulting from the racemisation can easily be isolated and purified, and the racemisation method can be implemented in volume such that the invention is economic.