Stereochemistry of copper(I) complexes. Part II. The molecular structure of the 3 : 2 reaction product between copper iodide and bis(diphenylphosphino)methane: di-µ-[bis(diphenylphosphino)methane]-µ-iodo-di-µ3-iodo-triangulo-tricopper(I)–0.5 dichloromethane

The crystal structure of the title compound has been determined from three-dimensional X-ray data by the heavy-atom method and refined by anisotropic block-diagonal least-squares to R 0.056 for 3 504 independent reflections. Crystals are monoclinic, space group P21/c, with cell parameters a= 13.266(8), b= 22.667(9), c= 20.887(8)Å, β= 121.94(7)°, Z= 4. The structure consists of a triangle of distorted tetrahedral copper atoms connected by a bridge of iodine atoms and the dpm ligand. Values of Cu–P and Cu–I bond lengths and the geometry of the halogen bridges are discussed on the basis of the structural results of similar compounds.