Dicyanamido-metal(II) complexes. Part 6: 1D polymeric copper(II) complexes bridging by dicyanamide. Effect of copper(II) salt on the nature of the polymeric product

The complexes {[Cu(L)(μ1,5-dca)](ClO4)}n (1, L = bepza; 2, L = bedmpza) and [Cu(L)(μ1,5-dca)(dca)]n (3, L = bepza; 4, L = bedmpza), where dca = dicyanamide anion, bepza = bis[2-(1-pyrazolyl)ethyl)]amine and bedmpza = bis[2-(di-2,5-dimethyl-1-pyrazolyl)ethyl)]amine, were synthesized and characterized by spectroscopic techniques. The crystal structures of complexes 1 and 3 confirmed their polymeric 1D chain nature through the two terminal nitrile groups of the μ1,5-bridging dicyanamido ligand. The magnetic susceptibility measurements of the two complexes 1 and 3 revealed the occurrence of very weak antiferromagnetic coupling with J values of −0.17 and −0.03 cm−1, respectively.