A new one-dimensional CdII coordination polymer with a two-dimensional layered structure incorporating 2-[(1 H-imidazol-1 -yl)methyl]-1 H-benzimidazole and benzene-1,2-dicarboxylate ligands

摘要

The N-heterocyclic ligand 2-[(1H-imidazol-1-yl)methyl]-1H-benzimidazole (imb) has a rich variety of coordination modes and can lead to polymers with intriguing structures and interesting properties. In the coordination polymer catewa-poly[[cadmium(II)-bis[/M-benzene-l,2-dicarboxylato-k~4O~1,O~1':O~2,O~2']-cadmium(II)-bis(μ-2-[(lH-imidazol-l-yl)methyl]-lH-benzimidazole}-k~2N~2:N~3;-k~2N~3:N~2] dimethylformamide disolvate], {[Cd(C_8H_4O_4)(C_(11)H_(10)N_4)]-C_3H_7NO}_n, (I), each CdII ion exhibits an irregular octahedral CdO_4N_2 coordination geometry and is coordinated by four O atoms from two symmetry-related benzene-1,2-dicarboxylate (l,2-bdic~(2-)) ligands and two N atoms from two symmetry-related imb ligands. Two CdII ions are connected by two benzene-1,2-dicarboxylate ligands to generate a binuclear [Cd_2(1,2-bdic)_2] unit. The binuclear units are further connected into a one-dimensional chain by pairs of bridging imb ligands. These one-dimensional chains are further connected through N—H---O hydrogen bonds and it-it interactions, leading to a two-dimensional layered structure. The dimethylformamide solvent molecules are organized in dimeric pairs via weak interactions. In addition, the title polymer exhibits good fluorescence properties in the solid state at room temperature.