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

Abstract

Reactions between the diphenylacetylenephosphine complexes cis-[M′Cl₂(PPh₂CCR)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-[(C₆F₅)₂M(µ-Cl)₂M′(PPh₂CCR)₂], (b) symmetric trans-palladium derivatives [{Pd(µ-Cl)(C₆F₅)(PPh₂CCR)}₂] and (c) the unusual chloride and diphenyl (phenylethynyl) phosphine bridged dinuclear compounds [(C₆F₅)₂Pt(µ-Cl)(µ-PPh₂CCPh)M′Cl(PPh₂CCPh)]. The complexes have been characterised by microanalysis, IR and NMR spectroscopy and the molecular structure of [(C₆F₅)₂Pt(µ-Cl)(µ-PPh₂CCPh)PtCl(PPh₂CCPh)]·OC₄H₈. The NMR spectral data (¹H, ¹⁹F and ³¹P) indicate that, in solution, mixtures of isomers [(C₆F₅)₂Pt(µ-Cl)₂M′(PPh₂CCR)₂] and [(C₆F₅)₂Pt(µ-Cl)-(µ-PPh₂CCPh)M′Cl(PPh₂CCPh)] are present.