By using Cu(OAc)2/TMEDA as the catalyst and air as the direct oxidant, arylboronic acids and diethyl phosphite can readily undergo an aerobic oxidative C—P coupling reaction under air at room temperature to give the useful arylphosphonates. This reaction uses relatively cheaper and less toxic copper salts as the catalyst, tolerates moisture and aerobic conditions. is suitable for a comparatively broad scope of substrates, and can give the target arylphosphonates in high selectivities and good yields. In comparison with conventional metal-catalyzed C—P coupling reactions of aryl halides, it is a relatively mild and efficient method for the synthesis of arylphosphonates.