Lanthanide-catalyzed regio- and enantioselective hydrosilylation of aryl-substituted terminal and internal alkenes

A highly regio- and enantioselective hydrosilylation of aryl-substituted terminal and internal alkenes with primary silanes was achieved using a chiral La(iii)-bisoxazoline complex. Regardless of the configuration of the alkenes, various secondary silanes were afforded in high yields with good enantioselectivities (up to 99% yield, 93 : 7 er) under low catalyst loading (as low as 0.5 mol%). Based on the structure of the catalyst, experimental studies and theoretical calculations, a possible reaction mechanism was proposed to understand the regio- and enantioselectivity.