Syntheses, Structures and Properties of Two Cd(II) Complexes Based on the 2-(1H-Imidazol-1-yl-methyl)-1H-benzimidazole Ligand

Two new 1-D Cd(II) complexes, {[Cd(imb)(μ2-Cl)Cl]·CH3OH}n (1) and {[Cd(imb)(μ2Cl)Cl]·DMF}n (2), have been synthesized by the reactions of the unsymmetrical ligand 2-(1Himidazol-1-yl-methyl)-1H-benzimidazole (imb) with CdCl2·2.5H2O in methanol or methanol/DMF solution at room temperature, and structurally characterized by single-crystal X-ray diffraction. Complex 1 displays a ladder-shaped chain in which [Cd2Cl4] units are linked to each other through two bridging imb ligands. Complex 2 features an infinite looped chain structure composed of two kinds of rings, the smaller [Cd2Cl2] ring and the larger [Cd2imb2] ring, connected alternately via their Cd(II) ions. The different architectures of complexes 1 and 2 can be generated by solvent exchange. The IR spectra and fluorescence properties of the complexes have been also investigated.