Hydrosilylation of Dihydrosilylium Ion Stabilized by Coordination of a σ‐Donating Ni(0) Ligand

Abstract

AbstractThe hydrosilylation reactions of dihydrosilylium ion 2, stabilized by coordination of a σ‐donating Ni(0) fragment, has been investigated. Complex 2 with two reactive sites, dihydrosilylium and Ni(0) centers, readily reacts with diphenylacetylene via a selective mono‐hydrosilylation reaction to afford the corresponding Ni(0)‐stabilized (hydro)(vinyl)silylium ion 6. In the case of ethylene, three equivalents of olefin are consumed to give a cationic Ni(II)‐complex 7 featuring a Bu‐Si+‐NiII‐Et moiety with a NHC‐supported Si atom. DFT calculations indicate that the hydrosilylation proceeds by a classical (Chalk‐Harrod type) mechanism with the assistance of NHC ligand moving between Si and Ni centers according to their stabilization requirements.