Synthesis of cyanoformamides from primary amines and carbon dioxide under mild conditions. Synthesis of ceratinamine

Treatment of primary amines with tetramethylphenylguanidine (PhTMG) and a cyanophosphonate at −10 °C under an atmosphere of carbon dioxide provides cyanoformamides in very high to excellent yields. The reaction proceeds efficiently within a short time. By-products were not detected in most runs and epimerization was not found when optically pure α-aminoesters were used as substrates. As an example, the reaction was applied to the synthesis of the marine natural product ceratinamine.