Cyclopentadienyl-ruthenium and -osmium chemistry. Part 20. Synthesis and X-ray structure of a cationic ruthenium–vinylidene complex, [Ru(CCHMe)(PMe3)2(η-C5H5)]PF6
The complexes [Ru(CCR)(PMe3)L(η-C5H5)](R = Me or Ph, L = PMe3: R = Ph, L = PPh3) were obtained from reactions between [Ru(CCR)(PPh3)2(η-C5H5)] and PMe3, while [Ru(CCHR)(PMe3)2(η-C5H5)]PF6(R = H, Me, or Ph) were formed from [RuCl(PMe3)2(η-C5H5)], HCCR, and NH4PF6. Alkylation of [Ru(CCPh)(PMe3)2(η-C5H5)] with OMe3PF6 gave [Ru(CCMePh)(PMe3)2(η-C5H5)]PF6. The molecular structure of [Ru(CCHMe)(PMe3)2(η-C5H5)]PF6 is described. It has the distorted ‘piano-stool’ configuration, with the plane of the vinylidene ligand bisecting the molecular symmetry plane. For the vinylidene ligand, Ru–C 1.845(7), C–C 1.313(10)Å, Ru–CC 180(2) and C–C–Me 125.1(6)°.