Reactions of metalloalkynes. New C2 bonding mode in a trimetallic complex

Abstract

The reaction of the silver complexes [{{Ru(CO)₂(η-C₅H₄R)}₂(μ-CC)}₃Ag₃][BF₄]₃ (R = H or Me) with [RuCl(CO)₂(η-C₅H₄R)] at room temperature gave the new trimetallic complexes [{Ru(CO)₂(η-C₅H₄R)}₃(η¹:η²-CC))][BF₄] which contain the C₂²⁻ ligand surrounded by ruthenium atoms; these complexes do not contain metal–metal bonds and were characterised by single crystal X-ray studies; the solid state structure is not retained in solution, where it is found to be fluxional on the NMR timescale and the dynamic process postulated could be described as ‘bearing-like’.