Synthesis, Spectral, Thermal Studies of Co(II), Ni(II), Cu(II) and Zn(II)-Arginato Complexes. Crystal Structure of Monoaquabis(arginato-kappa O,kappa N) Copper(II). [Cu(arg)(2)(H2O)]center dot NaNO3

Abstract

Transition metal complexes of arginine (using Co(II), Ni(II), Cu(II) and Zn(II) cations separately) were synthesized and characterized by FTIR, TG/DTA-DrTG, UV-Vis spectroscopy and elemental analysis methods. Cu(II)-Arg complex crystals was found suitable for x-ray diffraction studies. It was contained, one mole Cu-II and Na+ ions, two arginate ligands, one coordinated aqua ligand and one solvent NO3- group in the asymmetric unit. The principle coordination sites of metal atom have been occupied by two N atoms of arginate ligands, two carboxylate O atoms, while the apical site was occupied by one O atom for Cu-II cation and two O atoms for Co-II, Ni-II, Zn-II atoms of aqua ligands. Although Cu-II ion adopts a square pyramidal geometry of the structure. Co-II, Ni-II, Zn-II cations have octahedral due to coordination number of these metals. Neighbouring chains were linked together to form a three-dimensional network via hydrogen-bonding between coordinated water molecule, amino atoms and O atoms of the bridging carboxylate groups. Cu-II complex was crystallized in the monoclinic space group P2(1), a = 8.4407(5) angstrom, b = 12.0976(5) angstrom, c = 10.2448(6) angstrom, V = 1041.03(10) angstrom(3), Z = 2. Structures of the other metal complexes were similar to Cu-II complex, because of their spectroscopic studies have in agreement with each other. Copper complex has shown DNA like helix chain structure. Lastly, anti-bacterial, anti-microbial and anti-fungal biological activities of complexes were investigated.