Syntheses, Crystal Structures, and Properties of a Series of Coordination Polymers Based on 2-(n-Pyridyl)benzimidazole Ligands (n = 3, 4)

Abstract

Six new coordination polymers, namely, [Zn(3-PyHBIm)(oba)H2O] (1), [Cd(3-PyHBIm)(oba)H2O] (2), [Ni(3-PyHBIm)(oba)H2O]·3H2O (3), [Zn(4-PyHBIm)(oba)] (4), [Cd(4-PyHBIm)2(oba)]·H2O(5), and [Co(4-PyHBIm)2(oba)]·H2O (6) were synthesized under hydrothermal conditions based on 2-(n-pyridyl)benzimidazole (n-PyHBIm) and 4,4′-oxybis-(benzoate) (oba) ligands. The compounds were characterized by single crystal X-ray diffraction, IR, and thermogravimetric and elemental analyses. Compounds 1 and 2 contain simple one-dimensional (1D) polymeric chains assembled into a three-dimensional (3D) network through aromatic π–π stacking interactions and hydrogen bonding interactions. Compound 3 contains 1D polymeric chains with side arms which assembled into a two-dimensional (2D) network with channels and further assembled into a 3D network though C–H···π interactions. Compounds 4 and 5 form 1D molecular ladder coordination polymers. Compound 6 consists of 2D coordination networks with 2-fold interpenetration. The luminescence p...