Four New Coordination Polymers Constructed by 2-(4-Thiazolyl)benzimidazole and 1,3,5-Benzenetricarboxylic Acid

Abstract

Through using mixed N/S-containing ligand 2-(4-thiazolyl)benzimidazole (L), four new metal–organic coordination polymers, namely, [Co2 L 4(HBTC)(H2O)2] (1), [Cu2 L 2(HBTC)2]·H2O (2), [NiL 3]·(HBTC)·H2O (3) and [NiL 3]·H2O (4), have been synthesized under hydrothermal conditions, further assisted by a second organic ligand, benzenetricarboxylic (H3BTC). The structures of 1–4 have been determined by single crystal X-ray diffraction analyses and further characterized by elemental analyses and IR spectra. Compound 1 contains two {CoL 2(H2O)} fragments, which are connected by a BTC molecule to form a discrete “V”-type subunit. The hydrogen bonding interactions between N3⋯O1 atoms induce a 1D chain of 1. Complex 2 includes bi-nuclear CuII subunits, which are linked by BTC ligands to form a 2D layer. Each bi-nuclear Cu subunit is linked by four BTC molecules. Both complexes 3 and 4 are based on [NiL 3] subunits. In complex 3, when NiCl2·6H2O was used as reactant, a discrete BTC molecule is captured as a counter anion. In contrast, when using reactant NiSO4·6H2O, [NiL 3]·H2O (4) is formed. Both complexes 3 and 4 contain abundant hydrogen bonding interactions. In these complexes, the N donors in L ligand coordinate with transition metals and the S atoms participate in hydrogen bonding interactions. Through using mixed N/S-containing ligand 2-(4-thiazolyl)benzimidazole (L), four new metal-organic coordination polymers, namely, [Co2 L 4(HBTC)(H2O)2] (1), [CuL(HBTC)] (2), [NiL 3]·(HBTC)·H2O (3) and [Ni(L)3]·H2O (4), have been synthesized under hydrothermal conditions further assisted by the second organic ligand benzentricaboxylate (H3BTC).