The crystal structure of catena-μ-bis-(1,2-diphenylphosphinyl)ethane-dichlorocopper(II)

Abstract

The crystal structure of the compound with stoichiometry CuCl 2 . bis(1,2-diphenylphosphinyl)ethane has been determined from three dimensional X-ray diffraction data collected on a General Electric XRD-6 automatic diffractometer, using Cu-Kα radiation and the stationary crystal-stationary counter technique. The monoclinic cell for the greenish-blue crystals has dimensions of a = 12.206(2), b = 20.172(4), c = 10.559(1) Å and β = 97.26(2) Å. The space group is C2/c and, with 4 molecules per unit cell, D c 1.454 g/cm 3 and D m is 1.46 g/cm 3. The structure was determined by the heavy atom method and refined by full matrix least-squares techniques to a final R of 0.047 for the 2161 observed reflections used in the analysis. The Cu atom lies on a 2-fold axis and the bis(1,2-diphenylphosphinyl) ethane ligand lies on a center of symmetry. The crystal consists of infinite chains of CuCl 2 units linked by the phosphine oxide which is functioning as a bridging rather than chelating ligand. A comparison of the Cu-O distance of 1.959(3) Å with the value in other oxo-adducts reveals a remarkable consistency of Cu-O bonds lengths, while the Cu-Cl distances (2.195(1) Å in the present complex) vary depending on the nature of the oxomolecule. The fact the Cu-O distance is independent of the nature of the oxo donor molecule but that the Cu-Cl distances vary has not been noted previously.