Cobalt(II), silver(I), and lead(II) tetrabromoterephthalates exhibiting the 1-D linear chain, 2-D CdCl2-type layer, and 3-D penta-nodal mixed-connecting coordination frameworks

摘要

Reaction of tetrabromoterephthalic acid (H(2)TBTA) with Co(OAc)(2), AgNO3, or Pb(OAc)(2) under similar conditions affords three new coordination polymers {[Co(TBTA)(DMF)(2)(H2O)(2)](DMF)(2)}(n) (1), [Ag(TBTA)(0.5)](n) (2), and [Pb-2(TBTA)(1.5)(OH)(DMF)](n) (3). All these complexes have been characterized by elemental analysis, IR, powder X-ray diffraction, and TG-DTA techniques. Single-crystal X-ray diffraction reveals that complex 1 has a 1-D neutral coordination array in which the adjacent Co-II centers are bridged by the TBTA spacers, whereas 2 displays a binodal CdCl2-type coordination layer in which the Ag-I ions and TBTA ligands function as 3- and 6-connected nodes, respectively, In the structure of 3, two types of Pb-II ions are interconnected via the mu(4)- and mu(5)-TBTA ligands as well as the mu(3)-hydroxyl ions to generate a complicated 3-D penta-nodal coordination framework with (3,4,5)-connectivity. These results clearly suggest that the metal centers with distinct binding tendencies are responsible for the remarkable structural diversity of such crystalline materials.