Rhodium-catalyzed enantioselective C−Ge bond formation by carbene insertion: Efficient access to chiral organogermanes

Organogermanium compounds have shown potential as pharmaceuticals and functional materials and have been used as coupling partners in transition metal-catalyzed cross-coupling reactions. Methods for the synthesis of organic germanium compounds, including catalytic C−Ge coupling reactions and hydrogermylations of alkenes or alkynes, have been developed. However, the development of an efficient method for enantioselective C−Ge bond formation and synthesis of chiral organogermanium compounds remains a challenge, impeding the exploration of their functionalities. We herein report a highly enantioselective reaction for the formation of C−Ge bond catalyzed by chiral dirhodium phosphate catalysts, providing an efficient method for the synthesis of chiral organogermanes. The method features a broad substrate scope, good functional group tolerance, and mild reaction conditions. The mechanism of the C−Ge bond formation reaction was studied computationally and experimentally.