Synthesis, structural and magnetic properties, and catecholase activity of Cu(II) and related metal(II) complexes containing reduced Schiff base ligands

Abstract

Several copper(II) complexes with N-(2-hydroxybenzyl)aminoamides have been synthesized, structurally characterized, and their catecholase catalytic activities have been evaluated. The variable temperature magnetic properties of selected Cu(II) complexes have been studied. Several Cu(II) complexes containing N-(2-pridylmethyl)aminacids have been synthesized and characterized. The influences of solvent, alkali metals, pH and the nature of reactants have been investigated. Depending on the nature of the reactants used, a hexameric ring cation or an infinite 1D polymeric cation have been obtained for Cu(II) complexes of N-(2-pyridylmethyl)glycine. In the presence of KClO4, Cu(II) forms a cation containing Cu3K core with N-(2-pyridylmethyl)alanine in MeCN solvent, which decomposed to a 1D coordination polymer in the presence of moisture. N-(2-pyridylmethyl)histidine (Hphis) forms [LiCu3(phis)3]4+ with Cu(ClO4)2 in the presence of Li+, a trinuclear cation in the presence of Na+ or K+ in the pH range 5-7 or a 1D coordination polymer when the pH is 3. Complexes of these ligands with Zn(II) and Pb(II) were also synthesized and structurally characterized. The Pb(II) complex of N-(2-pyridylmethyl)alanine was found to form a 1D helical polymeric structure in the solid state.