Highly fluorous complexes of nickel, palladium and platinum: solubility and catalysis in high pressure CO2

Abstract

A variety of Group 10 metal complexes [MXY(dfppp)], M = Ni, X, Y = Cl, Br, M = Pd, Pt, X, Y = Cl or CH₃, containing the recently reported highly fluorous diphosphine ligand, dfppp, 1,3-bis[di(fluoroponytail)phosphino]propane, {(p-F₁₃C₆C₆H₄)₂P}₂(CH₂)₃ have been synthesised. They have been characterised by NMR, mass spectrometry and microanalysis, with two platinum complexes, [PtCl₂(dfppp)] and [PtClMe(dfppp)], structurally characterised by single crystal X-ray diffraction studies. The highly fluorous nature of the ligands affords the complexes good supercritical CO₂ solubility as measured by supercritical fluid extraction (SFE), and has allowed for the copolymerisation of CO and ethylene using [PdClMe(dfppp)] as the catalyst precursor and CO₂ as the solvent. Additionally, PtCl₂ complexes of the new ligands dfppb, {(p-F₁₃C₆C₆H₄)₂P}₂(CH₂)₄, and dfpop, {(p-F₁₃C₆C₆H₄O)₂P}₂(CH₂)₃, have also been prepared and characterised.