Metal-Free Direct Amidation Of Peptidyl Thiol Esters With Alpha-Amino Acid Esters

Metal-free direct amidation of peptidyl thiol esters with alpha-amino acid esters in the presence of bis(trimethylsilyl) acetamide (BSA) has been developed. This general method provides convenient access to N-protected peptides in good yields under mild conditions and demonstrates a high tolerance to functionality.