Abstract
The peptide bond formation reaction by some analogs of diphenyl phosphorazidate (DPPA) was investigated, proving that DPPA is much superior in the Young test to diethyl phosphorazidate, di-p-nitrophenyl phosphorazidate, dimorpholyl phosphorazidate, and diphenyl phosphorochloridate. Some spectroscopic investigations on the DPPA method were also made. Possible mechanisms for the DPPA method are presented in Chart 1.