Supramolecular assembly of a series of new coordination polymers based on 4,4′-(carbonylimino)dibenzoic acid: Syntheses, structures and photoluminescence investigation

Assembly reactions of acylamide-containing dicarboxylate ligand 4,4′-(carbonylimino)dibenzoic acid (H₂L) with corresponding divalent metal ions resulted in the formation of seven new coordination polymers, namely Cd(L)(H₂O) (1), Zn(L)(H₂O) (2), Zn ₅(L)₂(OH)₆ (3), [Ni(L)(H₂O) ₂]·H₂O (4), [Cd(L)(py)(H₂O)] ·(DMF)·(C₆H₅Cl) (5), [Cd(L)(py) ₂]·2CH₃OH (6) and [Mn (HL)₂(py) ₂]·2DMF (7). In complex 1, the double chains composed Cd ^II and L^2- are connected by interlayer Cd-O bonds to form a three-dimensional architecture. Complex 2 exhibits a three-dimensional supramolecular architecture extended by hydrogen bonds involving O-Hâ[;̄O and N-Hâ]̄O types. Complex 3 displays a three-dimensional framework consisting of zinc-hydroxide layers and L ^2- pillars. Complex 4 is also a supramolecular three-dimensional network generated from linkage of Ni-O chains via versatile hydrogen bonds. Complex 5 exhibits an interdigitated network in which the cavities are occupied by guest DMF and C₆H₅Cl molecules. In complex 6, two-dimensional square-grid network was generated by linkage of Cd₂ units with L^2- ligands. Mono-depronated ligand presents in complex 7. The adjacent [Mn(py)(HL)] chains are arranged parallel to each other by forming hydrogen bonding between the acylamide groups and guest DMF molecules. The stability properties of 2, 3, 4, 6 and 7 have been presented. In addition, photoluminescence properties of complexes 2, 3, 5 and 6 are investigated.