Copper-catalyzed direct oxyphosphorylation of alkynes with H-phosphine oxides and dioxygen: A convenient approach to -ketophosphine oxides

A simple and facile copper-catalyzed synthesis of -ketophosphine oxides via direct oxyphosphorylation of alkynes with H-phosphine oxides and dioxygen has been developed under mild conditions without any base or cocatalyst. A radical reaction pathway for the formation of -ketophosphine oxides is proposed. An O-18 labeling experiment suggested that the carbonyl oxygen atom of -ketophosphine oxides originated from dioxygen. [GRAPHICS] .