Reactions of alkynes with coordinatively unsaturated (.eta.5-C5Me5)Ru derivatives. X-ray crystal structures of (.eta.5-C5Me5)Cl2Ru(.eta.2:.eta.4-.mu.2-C4H4)Ru(.eta.5-C5Me5) and (.eta.5-C5Me5)3Ru3(.mu.2-Cl)2(.mu.3-Cl)(.eta.2-.mu.2-HC.tplbond.CSiMe3)

Abstract

Reaction of acetylene with Cp*Ru(P i Pr 3 )Cl or [Cp*Ru(μ 3 -Cl)] 4 (Cp*=η 5 -C 5 Me 5 ) gives good yields of the dinuclear ruthenacyclopentadiene complex Cp*Cl 2 Ru(η 2 :η 4 -μ 2 -C 4 H 4 )RuCp* (1). Alkylation of 1 with MeMgBr affords the dimethyl complex Cp*Me 2 Ru(η 2 :η 4 -μ 2 -C 4 H 4 )RuCp* (2). Reaction of [Cp*Ru(μ 3 -Cl)] 4 with Me 3 SiC≡CH produces the cyclobutadiene complex Cp*Ru[η 4 -C 4 H 2 (SiMe 3 ) 2 ]Cl (3). If [Cp*Ru(M 3 -Cl)] 4 is allowed to react with a limited amount of Me 3 SiC≡CH (ca. 1 equiv), a triruthenium cluster containing one alkyne ligand may be isolated in high yield. This compound, Cp* 3 Ru 3 (μ 2 -Cl) 2 (μ 3 -Cl)(η 2 -μ 2 -HC≡CSiMe 3 ) (5), is unstable in solution but was characterized in the solid state by X-ray crystallography