Copper-Catalyzed Direct Oxidative C-H Functionalization of Unactivated Cycloalkanes into Cycloalkyl Benzo[ b]phosphole Oxides.

The first simple and efficient Cu-catalyzed radical addition/cyclization of various unactivated cycloalkanes with diaryl(arylethynyl)-phosphine oxides has been developed, providing a general, one-step approach to construct a new class of important benzo[ b]phosphole oxides via sequential C-H functionalization along with two new C-C bond formations.