Unsaturated σ-hydrocarbyl transition-metal complexes. Part I. Tri-methyltin acetylides as sources of late transition-metal derivatives: metathesis, oxidative addition, and oxidative cleavage

Abstract

The reactions of the tin acetylides R₃Sn·C⋮CPh (R = Me or Et) with some low oxidation state complexes of Mo⁰, Mo^II, Co⁰, Rh^I, Ir^I, and Pt⁰ have been investigated. They fall into four classes : metathesis [e.g., with RhCl(CO)(PPh₃)₂→ Rh(C⋮CPh)(CO)(PPh₃)₂]; oxidative addition, with or without neutral ligand elimination [e.g., Ir(C⋮CPh)(CO)(PPh₃)₂→ Ir(C⋮CPh)₂(SnMe₃)(CO)(PPh₃)₂ or Pt(PPh₃)₂→ Pt(C⋮CPh)(SnMe₃)(PPh₃)₂]; metathesis and oxidative addition [e.g., IrCl(CO)(PPh₃)₂→ Ir(C⋮CPh)₂(SnMe₃)(CO)(PPh₃)₂]; and oxidative cleavage [e.g., {Mo(π-C₅H₆)(CO)₃}₂→ Mo(π-C₅H₅)(SnMe₃)(CO)₃]. The structures of the compounds are assigned on the basis of spectroscopic data. Complexes having both SnR₃ and acetylide units are regarded as mono-hapto-(PhC⋮C·M·SnR₃) rather than bi-hapto-([graphic omitted]SnR₃). Selected reactions of some of the new Rh, Ir, and Pt acetylides are described.