Seven Copper Coordination Polymers Based on 5-Iodo-Isophthalic Acid: Halogen-Related Bonding and N-Donor Auxiliary Ligands Modulating Effect

Abstract

A series of copper coordination polymers of [Cu3(OH)2(5-iipa)2(phen)3(H2O)·4.5(H2O)]n (1) [Cu(5-iipa)(phen)(H2O)]n (2), [Cu(5-iipa)(bpe)·2(H2O)]n (3), [Cu(5-iipa)(p-bix)]n (4), [Cu(5-iipa)(bbi)]n (5), [Cu2(5-iipa)2(bbi)·0.5(H2O)]n (6), and [Cu(5-iipa)(bpp)·H2O]n (7) (phen = 1,10-phenanthroline, bpe = 1,2-bis(4-pyridyl)ethane, p-bix = 1,4-bis(imidazol-1-ylmethyl)-benzene, bbi = 1,1′-(1,4-butanediyl)bis(imidazole), bpp = 1,3-bi(4-pyridyl)propane) were hydro(solvo)thermally synthesized through the reaction of divalent copper salts, 5-iodo-isophthalic acid (5-H2iipa), and N-donor ancillary ligands. Single-crystal X-ray diffraction analyses on these complexes revealed that noncovalent interactions were found to be predominant in constructing these supramolecular architectures. Compounds 1–5 all possess three-dimensional (3D) supramolecular structures based on O···I, I···I, I···π, and π···π interactions. Compound 6 exhibits a complicated three-dimensional (3D) framework with a new (6·72)2(63·72·8)2(63·78·82·92) topology, while 7 features a 3D 3-fold interpenetrating network with a (4,4)-connected (3.85)(32·83·9) topology. A systematically structural description of these polymers indicates both halogen-related interactions and N-donor auxiliary ligands have a significant effect on the coordination network assembly. Their thermal analysis, X-ray diffraction, and UV–vis absorption spectra have also been investigated as well.