Tf2O/DMSO-Promoted Umpolung Phosphorylation for C(sp2)–P or C(sp3)–P Bond Formation

We have developed an umpolung method utilizing the Tf2O/DMSO-based system for C(sp2)-P bond or C(sp3)-P bond formation. This method employs both P(O)-H and P(O)-OH compounds as phosphorus sources and demonstrates excellent compatibility with a wide range of Grignard reagents. Without the requirement of precious transition metals or additives, this one-pot protocol provides a practical and efficient synthetic pathway to a variety of aryl and alkyl phosphine oxides. The broad substrate scope and diverse synthetic applications highlight the practical utility of this method.