Syntheses and Crystal Structures of Three Cu(II) Complexes Based on 2,2′-(ethane-1,2-diyl)bis(1H-imidazole-4, 5-dicarboxylic Acid)

Three new complexes, [Cu(H4ebidc)(H2O)2] (1), [CuCl(H5edidc)]·1/2(bbe)·CH3OH (2) and [CuBr(H5edidc)]·1/2 (bbe)·CH3OH (3) (H6ebidc = 2,2′-(ethane-1,2-diyl)bis(1H-imidazole-4,5-dicarboxylic acid) bbe = 1,2-bis(2-benzimidazolyl) ethane), have been synthesized and characterized by elemental analysis, IR, and single-crystal X-ray diffraction. The results show that all of the complexes possess mononuclear structure and each tetradentate ligand coordinates to Cu(II) ion in chelating fashion. Their 3D structures are packed through the hydrogen bonds in the solid state. Moreover, their fluorescent properties have been investigated at room temperature.