Synthesis of N-Z, N ' formyl alpha-amino acid derived gem-diamines

A variety of N-carbobenzoxy, N'-formyl gem-diaminoalkyl derivatives have been obtained through Goldsmith-Wick reaction of Z-alpha-amino acid/peptide acid derived isocyanates with 96% HCOOH in presence of 4-dimethylaminopyridine (DMAP) as catalyst. The reaction proceeds to completion within 2-4 h and results in good yields of the products isolated as stable solids.