Direct regioselective phosphonation of heteroaryl N-oxides with H-phosphonates under metal and external oxidant free conditions

A direct C-H/P-H functionalization of heteroaryl N-oxides with H-phosphonates is described. A wide variety of heteroaryl phosphonates were obtained in up to 92% yield in a chemo-and regioselective manner, under oxidant and metal free conditions. This procedure features practicality, high efficiency, environmental friendliness and atom economy.