Multinuclear copper (II) complexes derived from reactions of copper dithiocarbamates with cupric salts; the magnetic, spectral and analytical investigation of reaction products

Abstract

The reactions between bis(N,N-dialkyl dithiocarbamato) copper(ll) complexes and the simple cupric salts CuX2, where X = Cl, Br, NO3, and NCS, were investigated, and the products obtained were characterised by their infra-red, XRD, U.V., and ESR spectra and by their elemental analyses and magnetic properties. A binuclear structure is postulated for the CuCl2 products on the basis of their magnetic properties. Elemental analyses indicate their Cu(dtc)2.CuCl2 formula (where dtc - dialkyl dithiocarbamate). From U.V. evidence, a trans-dichl oro structure with respect to the CuS2Cu skeleton is postulated, which allows the two copper atoms to adopt a configuration near planar. These CuCl2 products appear to be the first sulphur bridged binuclear copper(ll) complexes to have been isolated. No complete structural analysis was possible for the CuBr2 products. Their elemental analyses and magnetic properties confirm complex structures beyond simple interpretation. Low magnetic moments indicate Cu(I) or Cu(IIl) oxidation states may be present. Elemental analyses allow the possibility of some sort of oxy-compounds, having formed. The other cupric salts, Cu(NO3)2 and Cu(NCS)2, were found to be of little use in preparing new products, but some properties of the little investigated thiocyanate were recorded. The investigation of x-ray fluorescence techniques, to permit copper and sulphur analyses to be obtained for the products prepared in this thesis, is described. Considerable developmental work was required on the newly installed equipment. Meaningful sulphur analyses were not obtained, but satisfactory copper analyses were achieved.