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 co mplex, (NPm)(2)CuI, presenting a trigonal geometry around the Cu atom. The reaction of this new complex (or of its chloro analogue) with a C u-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 t hey are isostructural and retain the trigonal geometry around the meta l 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] comp lex. These values are discussed in terms of Cu ... Cu interactions ind uced by the electron donor ability of X and the bulk of the phosphine L.