Zinc-Catalyzed Hydrosilylation and Hydroboration of N-Heterocycles

The zinc hydride NacNacZnH (2) (NacNac = [Ar'NC(Me)CHC(Me)NAr'](-), Ar' = 2,6-Me2C6H3) catalyzes regioselective hydrosilylation and hydroboration of pyridines, including the hydroboration of phenanthroline. Mechanistic studies of hydrosilylation, including labeling, kinetic analysis, and density functional theory calculations, suggest the possibility of a reaction pathway based on hydride transfer from an out-of-sphere activated silane.