ZnII Coordination Poylmers Based on 2,3,6,7-Anthracenetetracarboxylic Acid: Synthesis, Structures, and Luminescence Properties

In Our efforts to investigate polydentate ligands bearing bulky backbones, we used a bulky ligand, 2,3,6,7-anthracenetetracarboxylic acid (H(4)ata), to react with Zn-II ions under different conditions, yielding four new coordination polymers{[Zn(ata)(0.5)(DMF)(H2O)]center dot DMF center dot H2O}(n) (1), {[Zn(ata)(0.5)(4,4'-bipy)(0.5)(DMF)]center dot DMF}(n) (2), {[Zn(ata)(0.5)(azpy)(0.5)(DMF)]center dot DMF}(n) (3), and {[Zn(ata)(0.5)(4,4'-bipy)(DMAC)]center dot(DMA)(0.5)}(n) (4) (DMF = N,N-dimethylformamide, 4,4'-bipy = 4,4'-bipyridine azpy = 4,4'-azopyridine, DMAC = N,N-dimethylacetamide. DMA = dimethylamine), which were characterized by 1R and single crystal X-ray diffraction. Complex 1 forms a two-dimensional (213) network with (4,4) topology assembled by ata(4-) ligands and Zn-II ions. Complexes 2 and 3 are three-dimensional (3D) frameworks with {8(3)}(2){8(5);10} topology containing infinite 2D networks pillared by 4,4'-bipy and azpy, respectively. Complex 4 takes a 2D structure with (4,4) net containing infinite one-dimensional chains constructed by Zn-II ions with 4,4'-bipy and ata(4-) ligands. These results show that the reaction of 2,3,6,7-anthracenetetracarboxylic acid with Zn-II in DMF tends to yield a layer structure which could be pillared by bipyridine-like ligands into 3D frameworks, and the final structure of the coordination polymer is greatly influenced by the solvent. Furthermore, the luminescence properties of 1-4 were studied in the solid state at room temperature.