Cyclopentadienyl-ruthenium and-Osmium Chemistry. IX. Some Substituted η1-Vinylidene and η1-Acetylide Complexes

Abstract

Reactions between RUCI(PPh3)2(η-C5H5), RuCI(L2)(η-C5H5)(L2 = dppm or dppe) or OsBr(PPh3)2-(η-C5H5) and the alk-1-ynes HC2R (R = Me, Pr, CO2Me, Ph, C6H4F-p or C6F5), in the presence of NH4PF6, NH4BF4 or NaBPh4, have given the corresponding cationic η1-vinylidene complexes [Ru(C=CHR)(PPh3)2(η-C5H5)]+,[Ru(C=CHPh)(L2)(η-C5H5)]+ or [Os(C=CHP~)(PPh3)2(η-C5H5)]+. These cations are readily deprotonated to give the corresponding η1-ethynyl derivatives Ru(C2R)-(PPh3)2(η-C5H5), Ru(C2Ph)(L2)(η-C5H5) or OS(C2Ph)(PPh3)2(η-C5H5). Addition of HPF6 or [R'3O]PF6 (R' = Me or Et) to the latter affords the vinylidene complexes containing C=CHR and C=CRR' ligands (R = Me, Pr, CO2Me, Ph, C6H4F-p or C6F5; R' = Me or Et), respectively. The vinylidene complexes are characterized by ν(CC) bands at c. 1650 cm-1 and the metal-bonded carbon (13C) resonance at c. 360 ppm.