Synthesis and characterization of four dicyanamide bridged copper(II) complexes with N2O donor tridentate Schiff bases as blocking ligands

Four copper(II) complexes have been synthesized and characterized by elemental analysis, IR and UV-Vis spectroscopy and X-ray crystallography. Dicyanamide acts as a purely μ-1,5-bridging ligand in complexes 1, 2 and 4, whereas in 3, two consecutive dicyanamide units serve as 1,3-bridging ligand and the third one exhibits end-to-end 1,5-bridging mode.