Synthesis, characterization and thermal properties of 1,10-phenanthroline mixed-ligand complexes of cobalt(II) and copper(II): metal-mediated transformations of the dicyanamide ion

The reaction of 1,10-phenanthroline and dicyanamide ligands with Cu(II) and Co(II) nitrates afforded the complexes [Cu(phen)(BMCA)](NO3)] (1) and [Co(phen)2(NO3)](dcg-)·(H2O) (2). The dicyanamide anion was transformed in 1 and 2 to bis(methoxycarbimido)aminato (BMCA) and dicyanoguanidinate (dcg) anions, respectively. The complexes were characterized by elemental analysis, infrared spectroscopy and ultraviolet–visible spectroscopy, magnetic susceptibility measurement and X-ray crystallography. Both complexes crystallize in the monoclinic crystal system, and the structures are stabilized by extended hydrogen bonding networks as well as aromatic π–π stacking interactions. The thermal and antimicrobial properties of the complexes have also been evaluated. Density functional theory calculations were also performed in order to gain insights into the molecular interactions in the synthesized compounds and to predict some of their electronic properties.