Synthesis and characterization of copper(II) and nickel(II) coordination polymers containing 2,6-naphthalenedicarboxylate and bis(benzimidazole) ligands

Two coordination polymers, namely [Ni(L1)-(ndc)(H2O)] (n) (1) and [Cu(L2)(0.5)(ndc)] (n) (2) (L1 = 1,3-bis(2-methylbenzimidazol-1-ylmethyl)benzene, L2 = 1,4-bis(2-methylbenzimidazole)butane, H(2)ndc = 2,6-naphthalenedicarboxylic acid) have been synthesized and characterized by single-crystal and powder X-ray diffraction, IR spectroscopy, thermogravimetric analysis, and elemental analysis. Complex 1 features a 2D 3-connected hcb network with 6(3) topology, which is further extended into a 3D supramolecular framework by O-H center dot center dot center dot O hydrogen bonding interactions. Complex 2 possesses a 3D threefold interpenetrating (4,5)-connected xah topological network, and its Schlafli symbol is (4(2).6(2).8(2))(4(6).6(4)). Both complexes exhibit intense luminescence emissions in the solid state and promising catalytic activities for the degradation of Congo red azo dye in a Fenton-like process.