Facial conversion of secondary phosphine oxides R1R2P(O)H to chlorophosphines R1R2PCl by acetyl chloride

A practically useful protocol for the reductive transformation of secondary phosphine oxides R1R2P(O)H to chlorophosphines R1R2PCl using acetyl chloride was disclosed. Various secondary phosphine oxides could be readily reduced to the corresponding chlorophosphines in high yields under mild conditions.