Regioselective 1,2-Hydrosilylation of N‑Heterocycles Catalyzed by a Ruthenium Olefin Metathesis Catalyst

First-generationruthenium-indenylidene olefin metathesiscomplex catalyzes the 1,2-hydrosilylation reaction to access dihydroquinolinederivatives with high regioselectivity under mild conditions. Theruthenium-indenylidene complex was shown to have excellentcatalytic efficiency when the challenging Ph2SiH2 hydride donor is used. The reaction is efficient at 0.25-1mol % catalyst loadings with a wide range of quinoline derivativesand N-heterocycles. A mechanism for this transformation is proposedbased on stoichiometric reactions.