Binuclear pentafluorophenyl complexes containing halide and/or bis(diphenylphosphino)methane (dppm) as bridging ligands. Molecular structure of [N(PPh3)2][Pt2(µ-I)(µ-dppm)(C6F5)4]·2CHCL3

Abstract

The reaction of [N(PPh₃)₂]₂[Pt₂(µ-X)₂(C₆F₅)₄](X = Cl, Br or I) with bis(diphenylphosphino)methane (dppm) at room temperature in CH₂Cl₂ affords [N(PPh₃)₂]₂[(C₆F₅)₂XPt(µ-dppm)PtX(C₆F₅)₂](X = Cl 1, Br 2 or I 3) in good yield as the kinetic products. Further reactions between 1–3 and AgClO₄(molar ratio 1 : 1) in acetone–tetrahydrofuran render the corresponding derivatives [N(PPh₃)₂][(C₆F₅)₂Pt(µ-X)(µ-ddppm)Pt(C₆F₅)₂][X = Cl, Br or I) and AgX. These complexes are very stable, and the bridging system is not cleaved by anionic (X^–) or neutral ligands (NCMe, tetrahydrothiophene, SPPh₃, PPh₃). The structure of [N(PPh₃)₂][Pt₂(µ-I)(µ-dppm)(C₆F₅)₄]·2CHCl₃ has been determined by a single-crystal X-ray diffraction study, showing strain in the bridging (µ-X)(µ-dppm) system. Crystals are triclinic, space group P, with a= 11.609(2), b= 19.113(2), c= 19.997(2)Å, α= 101.83(1), β= 93.32(1), γ= 92.61(1)°, Z= 2; 8052 data with I > 3σ(I) refined to R= 0.051, R′= 0.068.