Mononuclear and dinuclear copper(I) complexes with a particularly bulky phosphine ligand. Unusual synthesis and crystal structure characterizations

The addition of NPm (diphenylaminodiphenylphosphinomethane) to CuI or the addition of KI to (NPm)(2)CuNO3 leads to the same P-bonded Cu-I complex, (NPm)(2)CuI, presenting a trigonal geometry around the Cu atom. The reaction of this new complex (or of its chloro analogue) with a Cu-II salt yields dinuclear species of general formula [(NPm)Cu(mu-X)(2)Cu(NPm)] (X = Cl or I). X-ray analysis of these complexes show that they are isostructural and retain the trigonal geometry around the metal atom. The Cu ... Cu distances are 2.775(1)Angstrom for X = Cl and 2.642(1)Angstrom for X = I. The Cu-(mu-X)-Cu angle is more acute for the iodide [61.48(3)degrees] than for the chloride [74.17(8)degrees] complex. These values are discussed in terms of Cu ... Cu interactions induced by the electron donor ability of X and the bulk of the phosphine L.