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

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.