Studies of Unusual Amino Acids and Their Peptides. XV. The Chemistry of N-Carboxymethyl Amino Acids. III. The Synthesis of N-Tosyl-N-carboxymethyl Amino Acid Derivatives by N-Alkoxycarbonylmethylation

Abstract
The alkoxycarbonylmethylation of the amide nitrogen of N-tosyl amino acid esters with iodoacetic acid esters in the presence of silver(I) oxide in N,N-dimethylformamide afforded the corresponding N-tosyl-N-carboxymethyl amino acid esters in good yields without racemization of the amino acids.