Pd- and Photo-Promoted C−H Functionalizations of Phospholes

Abstract Significant research efforts have been devoted to the synthesis of substituted phospholes due to their exceptional optical and physical properties. In contrast to conventional methods, the direct C−H functionalizations of readily accessible phospholes offer an efficient and modular route to structurally diverse phosphole derivatives. In this account, we present our research group’s advancements in the regioselective C−H functionalizations of benzophospholes, including: (1) palladium-catalyzed C−H arylation, alkenylation, and alkynylation; (2) organophotoredox-catalyzed C−H alkoxycarbonylation, phosphinylation, and alkylation; and (3) related photo-promoted dehydrogenative cyclization and palladium-catalyzed annulative π-extension.