Copper(II) complexes of aryl-aci-nitromethanes

Abstract

The copper(II) complexes, CuL₂, of aryl-aci-nitromethanes (LH = RR?CNO₂H; R? = H, R = C₆H₅, p-CH₃C₆H₄, or o-CH₃C₆H₄; R = R? = C₆H₅) have been examined. The magnetic and spectroscopic properties of the solids are consistent with planar, four-coordinate chelate structures with weak intermolecular interactions. In donor solvents six-coordinate adducts are formed; CuL₂(py)₂(R = C₆H₅) has been isolated and CuL₂(DMSO)₂ (R = C₆H₅) shown to occur in benzene-dimethyl sulphoxide solutions; the free energy of formation of the dimethyl sulphoxide adduct is comparable to that of base adducts of copper(II) β-diketone complexes.