Synthesis of alpha-amino acid precursors directly from aldehydes using masked acyl cyanide reagents and N,O-dialkylated hydroxylamines.

A synthetic methodology for the synthesis of alpha-amino acid precursors directly from the corresponding aldehydes using N,O-dialkylated hydroxylamines and masked acyl cyanide (MAC) reagents was developed. The one-pot reaction can be carried out under mild conditions and without a separate purification step of the imino species. The method was applied to the synthesis of optically pure (+)-4-methylphenylglycine and the derivatives by using an Abiko-Masamune's tricyclic 1,2-oxazolidine as the chiral auxiliary.