Metallaborane chemistry. Part II. Molecular and crystal structure of 1,1-bis(dimethylphenylphosphine)-2,4-dimethyl-2,4-dicarba-1-platina-closo-dodecaborane

The structure of the title compound has been determined by single-crystal X-ray diffraction methods and refined to R 0.033 for 4073 independent observed reflections collected on a diffractometer. Crystals are triclinic, space group P1, with a = 9.324(3), b = 10.285(4), and c = 14.208(8) Å, α = 100.40(4), β = 94.32(4), and γ = 98.95(3)°. The carbaborane fragment has a distorted icosahedral geometry with the carbon atoms at positions 2 and 4 (relative to the metal at 1). The platinum atom is ca. 1.81 Å above a (non-planar) C₂B₃ face which in turn is nearly perpendicular to the PtP₂ plane. Pt-P Distances are 2.249(2) and 2.303(2) Å. All the hydrogen atoms in the molecule have been located and positionally refined.