Copper-catalyzed C-P cross-coupling of arylmethyl quaternary ammonium salts via C-N bond cleavage

A ligand-free copper-catalyzed C-P cross-coupling reaction of arylmethyl quaternary ammonium salts and diarylphosphine oxides in air is developed. Arylmethyl quaternary ammonium salts with various functional groups and a variety of dialkyl- and diarylphosphine oxides afford C-P cross-coupling products with good yields. This protocol requires no inert atmosphere, no ligand, and simple operation steps.