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, H₂ndc = 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 6³ topology, which is further extended into a 3D supramolecular framework by O–H···O hydrogen bonding interactions. Complex 2 possesses a 3D threefold interpenetrating (4,5)-connected xah topological network, and its Schläfli symbol is (4².6².8²)(4⁶.6⁴). 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.