Acetato, formato and chloride copper(II) complexes with 2-(aminomethyl)pyridine: Synthesis, crystal structure, magnetic properties and EPR results

Abstract

By the reactions of Cu(OAc) 2 · H 2O and Cu(HCOO) 2 · 4H 2O with 2-(aminomethyl)pyridine in different proportions, the compounds Cu(OAc) 2(2-amp) ( 1), Cu(HCOO) 2(2-amp) ( 2), Cu(HCOO) 2(2-amp) 1/2 ( 5), Cu(OAc) 2(2-amp) 2 · H 2O ( 6) and Cu(HCOO) 2(2-amp) 2 · H 2O ( 7) were obtained. In 1 the copper shows an elongated rhombic octahedral stereochemistry determined by a 2-amp molecule and two asymmetrical bidentate acetate groups. The hydrogen bonds between the NH 2 groups and O atoms yield to the formation of a double chain. Compound 2 instead consists in monodimensional chains of Cu(2-amp)(HCOO) units, with monodentate formate groups, linked by syn–anti bridging formate groups. Sheets are formed by hydrogen bonds between the chains. By crystallization of a solution of 6 in chloroform, CuCl 2(2-amp) 2 ( 3) was obtained. It presents a highly distorted square pyramidal geometry around the copper atom. The sheets, formed by the hydrogen bonds between NH 2 and Cl, are interpenetrated and shows π stacking. Magnetic properties and EPR spectra for these new compounds have been studied. Also the magnetic behaviour of Cu(OAc) 2(2-amp) 1/2 ( 4) is described.