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

By the reactions of Cu(OAc)2 · H2O and Cu(HCOO)2 · 4H2O 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 · H2O (6) and Cu(HCOO)2(2-amp)2 · H2O (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 NH2 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, CuCl2(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 NH2 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.