Ir4(CO)12-Catalyzed Benzylic C(sp3)-H Silylation of 2-Alkylpyridines with Hydrosilanes Leading to 2-(1-Silylalkyl)pyridines

The iridium-catalyzed C(sp(3))-H silylation of 2-alkylpyridines with hydrosilanes at the benzylic position to afford 2-(1-silylalkyl)pyridines is described. The low product yield was markedly improved by adding 3,5-dimethylpyridine. Norbornene is also an essential additive for the reaction to proceed as a hydrogen scavenger. Carbon monoxide plays an important role in the catalytic cycle as a ligand. Other transition-metal carbonyls such as Rh-4(CO)(12) and Ru-3(CO)(12) can also be used as catalysts for this C-H silylation.