FUNKTIONELLE TRIMETHYLPHOSPHANDERIVATE. XIX. PHOSPHINOMETHYLSUBSTITUIERTE ZIRCONIUMVERBINDUNGEN ALS NUCLEOPHILE: SYNTHESE, REAKTION MIT CO UND MOLEKUELSTRUKTUR VON 2Ni

Article abstract of DOI:10.1016/0022-328X(84)80524-0

The organozirconium-substituted phosphines Cp2Zr(X)CH2PMe2 (Cp = η⁵-C5H5; X = Cl, CH2PMe2) have been prepared from Cp2ZrCl2 and LiCH2PMe2.In these compounds, the phosphinomethyl group acts as a monohapto (η¹-) ligand.On reaction with CO, the bis(phosphinomethyl)zirconium complex forms a red complex, which by means of NMR spectroscopy is shown to contain a novel zircona heterocycle.With Ni(COD)2, Cp2Zr(CH2PMe2)2 forms the 2:1 complex 2Ni.Crystals (from tetrahydrofuran) are triclinic, space group P<*>, with parameters a 13.433(5), b 18.062(3), c 19.505(2) Angstroem, α 64.35(2), β 76.82(1), γ 71.28(2) deg, V 4018.12 Angstroem³, d_x 1.445 g cm^-3 for Z = 4, μ(Mo-K_α) 11.5 cm^-1, T 21 deg C.Refinement of 743 parameters on 8826 reflections converged at R = 0.055.The molecular structure consists of monomeric units with two bidentate Cp2Zr(CH2PMe2)2 molecules acting as chelating ligands to a tetrahedral Ni⁰ centre.The six-membered Zr(CH2PMe2)2Ni rings adopt a chair conformation.Steric strain by interaction of the axial cyclopentadienyl and methyl ligands at Zr and P, respectively, causes these rings to be considerably flattened.