SYNTHESIS AND CHARACTERIZATION OF MIXED-LIGAND COMPLEXES OF COPPER(II), NICKEL(II), COBALT(II) AND ZINC(II) WITH GLYCINE AND THYMINE OR ADENINE

The mixed ligand complexes of Cu(II), Ni(II), Co(II) and Zn(II) formed with glycine and thymine or adenine have been synthesized and characterized by the elemental analysis, conductance, spectral (IR and electronic spectra) and magnetochemical measurements. The results prove that all the ligands are bidentate. In Cu(II) and Co(II) complexes with thymine the coordination between one ring nitrogen and carbonyl oxygen was established, whereas in the Ni(II) complex the bonding takes place between both ring nitrogens. In the Zn(II) complex there was a bonding between ring nitrogen and one carbonyl oxygen, but while one thymine coordinates at the C(2)O position, the other does at C(4)O. The coordination with adenine takes place at the N(3) and N(9) positions through the, deprotonation of N(9) - H. All these mixed complexes are octahedral, but the mixed Zn(II) complex with adenine is probably tetrahedral.