Organophosphorus compounds have been of particular interest due to their broad applications in organic synthesis,materials,bioorganic and medical chemistry,coordination chemistry and catalysis,and flame retardants.The synthesis of various organophosphorus compounds has been well documented.For examples,the Michaelis-Arbuzov reaction provides an efficient protocol for the synthesis of alkylphosphonates,and the transition-metal-catalyzed C-P cross-coupling reaction has been developed for the synthesis of arylphosphonates and their derivatives.It is noteworthy that trivalent arylphosphines,which have been widely used in metal-catalyzed reactions as ligands and organic synthesis,can be facilely prepared by a reduction of phosphine oxides.Herein,we report a novel insertion of arynes into the P-H bond of dialkyl phosphites and secondary phosphine oxides,which affords dialkyl arylphosphonates and tertiary phosphine oxides in good to high yields under mild conditions(Scheme 1).