Double Deprotonation of a Cationic Ruthenium(II) Terminal Vinylidene Complex and Molecular Structures of the Terminal Vinylidene Complex [(η5-C5Me5)(PPh3)2Ru(CCH2)]PF6 and the Acetylide Complex (η5-C5Me5)(PPh3)2Ru(C⋮CSiMe3)

(η 5 -C 5 Me 5 )(PPh 3 ) 2 Ru(Cl) (1) reacted with HC⋮CSiMe 3 in the presence of NH 4 PF 6 to afford the cationic Ru(II) terminal vinylidene complex, [(η 5 -C 5 Me 5 )(PPh 3 ) 2 Ru( C CH 2 )]PF 6 (2), in 73% yield. The terminal vinylidene complex 2 was doubly deprotonated with t -BuLi to generate the reactive lithioacetylide complex, (η 5 -C 5 Me 5 )(PPh 3 ) 2 Ru(C⋮CLi) (4), which was trapped with Me 3 SiCl and MeI to give (η 5 -C 5 Me 5 )(PPh 3 ) 2 Ru(C⋮CSiMe 3 ) (5) and (η 5 -C 5 Me 5 )(PPh 3 ) 2 Ru(C⋮CMe) (6) in 86 and 39% yields, respectively. The molecular structures of 2 and 5 were determined by X-ray crystallography.