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Updated: Jun 25, 2026
Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
Influence of solvent on the structures of two one-dimensional cobalt(II) coordination polymers with
Yong Qin Fang1, Ming Lu, Chun Xu Lu
1School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210093, People's Republic of China. yongqinfang@gmail.com
Abstract:
The title cobalt coordination polymers, catena-poly[[[aquatripyridinecobalt(II)]-mu-tetrachloroterephthalato] pyridine solvate], {[Co(C(8)Cl(4)O(4))(C(5)H(5)N)(3)(H(2)O)].C(5)H(5)N}(n), (I), and catena-poly[[[diaquadipyridinecobalt(II)]-mu-tetrachloroterephthalato] 1,4-dioxane trihydrate], {[Co(C(8)Cl(4)O(4))(C(5)H(5)N)(2)(H(2)O)(2)].C(4)H(8)O(2).3H(2)O}(n), (II), have been prepared with tetrachloroterephthalic acid (H(2)BDC-Cl(4)) under different solvent media. Both complexes form infinite cobalt(II)-tetrachloroterephthalate polymeric chains. In (I), two independent Co(II) ions are six-coordinated through N(3)O(3) donor sets in slightly distorted octahedral geometries provided by two carboxylate and three pyridine ligands, and one water molecule. The structure of (II) contains two independent Co(II) atoms, each lying on a twofold axis, which adopt a tetragonally distorted N(2)O(4) octahedral geometry via two carboxylate groups, two pyridine ligands and two water molecules. The different stoichiometry of coordinated and solvent guest molecules leads to different two-dimensional supramolecular networks, with (I) utilizing C-H...pi and weak pi-pi interactions and (II) utilizing mainly conventional hydrogen bonding.
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