Well-Defined Rhodium Diphenylphosphine Oxide Complexes Relevant to Rh(III)-Catalyzed Aryl C–H Phosphorylation

Secondary phosphine oxides (SPOs) are often difficult coupling partners for transition-metal-catalyzed C–H phosphorylation reactions. Herein, a series of SPO-RhIIIcomplexes relevant to RhIII-catalyzed C–H phosphorylation was isolated and fully characterized. Detailed research on their reactivities in C–H rhodation indicates the crucial role of a suitable base to reduce the deactivation of RhIIIby SPOs. Finally, using silver carbonate as both a base and an oxidant, an efficient RhIII-catalyzed aryl C–H phosphorylation with diarylphosphine oxides was developed.