Multifunctional 1,3-diphenylguanidine for carboxylative cyclization of homopropargyl amines with CO2 under ambient temperature and pressure

Herein, we report the 1,3-diphenylguanidine (DPG) could be utilized for the carboxylative cyclization of homopropargyl amine with CO2 at ambient temperature and pressure, with the combination of AgSbF6, which enable the synthesis of both chiral and achiral 2-oxazinones efficiently. Mechanistic-study reveals the multi-functionality of DPG is critical to the success.