An efficient conversion of the carboxylic group of N-Fmoc α-amino acids/peptide acids into N-formamides employing isocyanates as key intermediates

(Chemical Equation Presented) Reaction of 96 formic acid with isocyanates derived from N-Fmoc α-amino acids/peptide acids catalyzed by DMAP has yielded a new class of stable formamides as crystalline solids which have been characterized by IR, 1H NMR, 13C NMR, and mass spectroscopy. Conversion of the side chain carboxylic acid of N-Fmoc-5-oxazolidinones of Asp/Glu into the N-formyl group also has been accomplished. The reaction is simple, mild, and high yielding. © 2007 American Chemical Society