SYNTHESIS AND SPECTROSCOPIC INVESTIGATION OF MIXED-LIGAND COPPER-CHELATES CONTAINING 2-HYDROXYARYLOXIMES AND N-DISUBSTITUTED DITHIOCARBAMATES - CRYSTAL AND MOLECULAR-STRUCTURE OF TRANS-BIS[PROPANONE, 1-(2-HYDROXY-PHENYL)OXIMATO]COPPER(II)

A series of mixed-ligand copper(II) chelates containing the anion of 2 -hydroxyaryloxime(oxime) and N,N-disubstituted dithiocarbamate(dtc), [ Cu(dtc)(oxime)], was prepared and characterised. The spectra (IR, ESR, electronic excitation) indicate that the CuNOS2 chromophore attains s quare planar geometry. The ESR observables suggest appreciable covalen cy. In the case of [Cu(Et(2)dtc)(oxime)] chelates, however, the observ ed data suggest distortion from square planar arrangement to a square pyramidal, indicative of a possible dimerism. In addition, the structu re of the trans-bis[propanone, 1-(2-hydroxyphenyl)-oximato]copper(II), Cu(C9H10NO2)(2) was determined by X-ray diffraction (monoclinic, spac e group P2(1)/n, a=12.072(7) Angstrom, b=5.204(2) Angstrom, c=13.571(6 ) Angstrom, beta=103.72(1)degrees, Z=2). The molecule consists of disc rete Cu(ppox)(2) monomeric units, where the Cu atom is in the equatori al plane bonded to two nitrogen atoms and two oxygen at distances of 1 .949(2) and 1.882(2) Angstrom, respectively.