Amino acids and peptides. XXIX. A new efficient asymmetric synthesis of .ALPHA.-amino acid derivatives with recycle of a chiral reagent - asymmetric alkylation of a chiral Schiff base from glycine.

An efficient asymmetric synthesis of D-α-amino acid derivatives (VI) has been achieved by alkylation of the Schiff base (III), prepared from glycine tert-butyl ester and (1S, 2S, 5S)-2-hydroxypinan-3-one (II), followed by hydrolytic cleavage of the alkylated Schiff base (V). The chiral source (II) was also recovered in good yield, allowing the proliferation of the asymmetry according to the cycle of the amino acid asymmetric synthesis shown in Chart 1.