Homo- and hetero-dinuclear complexes of palladium and platinum containing phosphinoacetylene and/or chloride as bridging ligands

Reactions between the diphenylacetylenephosphine complexes cis-[M'Cl₂(PPh₂C=CR)₂] (M' = Pt or Pd, R = Ph or Bu^t) and cis-[M(C₆F₅) ₂(thf)₂] (M = Pt or Pd; thf = tetrahydrofuran) in a 1:1 molar ratio have been studied. Three types of products have been obtained: (a) asymmetric homo- and hetero-dinuclear complexes gem-[(C₆F ₅)₂M(µ-Cl)₂M' (PPh₂C= CR)₂], (b) symmetric trans-palladium derivatives [{Pd(µ-Cl) (C₆F₅) (PPh₂C=CR)}₂] and (c) the unusual chloride and diphenyl (phenylethynyl) phosphine bridged dinuclear compounds [(C₆F₅)₂Pt(µ-Cl)(µ-PPh ₂C=CPh)M'Cl(PPh₂C=CPh)]. The complexes have been characterised by microanalysis, IR and NMR spectroscopy and the molecular structure of [(C₆F₅)₂Pt(µ-Cl) (µ-PPh₂C=CPh)PtCl(PPh₂C=CPh)] ·OC₄H₈. The NMR spectral data (¹H, ¹⁹F and ³¹P) indicate that, in solution, mixtures of isomers [(C₆F₅)₂Pt(µ-Cl)₂M' (PPh₂C=CR)₂] and [(C₆F₅) ₂Pt(µ-Cl)-(µ-PPh₂C=CPh)M'Cl(PPh ₂C=CPh)] are present.