Cyclopentadienyl-ruthenium and -osmium chemistry. X. Reactions of vinylidene complexes with alcohols and water: syntheses of alkoxy(alkyl)carbene, acyl and alkyl complexes

Abstract

Simple ligand-exchange reactions between Ru(C₂Ph)(PPh₃)₂(η-C₅H₅) and L afford Ru(C₂Ph)(L)-(PPh₃)(η-C₅H₅) [L = CO, CNBu^t, PMe₃ or P(OMe)₃]. These complexes, and other σ-acetylides, Ru(C₂R)(PPh₃)₂(η-C₅H₅) (R = Me or CO₂Me), react with HPF₆,OEt₂ to give the corresponding vinylidene complexes {Ru(C=CHPh)(L)(PPh3)(η-C₅H₅)]PF₆ or [Ru(C=CHR)(PPh₃)₂(η- C₅H₅)}PF₆; which in turn react more or less readily with MeOH to give {Ru[C(OMe)CH₂Ph](L)(PPh₃)(η-C₅H₅)]PF₆ or {Ru[C(OMe)CH₂R](PPh₃)₂(η-C₅H₅)}PF₆; the complexes {Ru[C(OR)CH₂Ph](CO)(PPh₃)-(η-C₅H₅)}PF₆ (R = Et or Prⁱ) and {Ru[C(OMe)CH₂Ph](dppe)(η-C₅H₅)}PF₆ were formed in analogous reactions. Water reacts with [Ru(C=CHPh)(L)(PPh₃)(η-C₅H₅)]PF₆ to give RuX(CO)(PPh₃)(η-C₅H₅) (L = PPh₃, X = CH₂Ph; L = CO, X = COCH₂Ph), the former being formed by a spontaneous alkyl migration reaction.