Enantioselective construction of Si-stereogenic linear alkenylhydrosilanes via copper-catalyzed hydrosilylation of alkynes

Summary

Enantiopure organosilicon compounds are currently applied in various areas, such as bioactive molecules and organic materials. However, enantioenriched silicon-stereogenic compounds do not exist in nature. Exuberant interest has prompted chemists to synthesize and apply these particular compounds. Herein, we report a copper-catalyzed asymmetric hydrosilylation of alkynes with dihydrosilanes for the synthesis of silicon-stereogenic alkenyl silanes in good regio- and enantioselectivities. Demonstrated by a diverse collection of substrates, the process grants access to chiral alkenylhydrosilanes with a simple Cu/(S)-Tol-BINAP catalytic system. The origin of the enantiocontrol was investigated by density functional theory (DFT) calculations, which revealed a quite complicated scenario involving multiple pairs of diastereomeric transition structures accounting for the high enantiocontrol under the seemingly simple conditions.