Design and construction of six metal–organic frameworks with 2-p-methoxyphenyl-1H-imidazole-4,5-dicarboxylate

Abstract

Six novel transition-metal–organic frameworks, [Cu(μ2-HMOPhIDC)(H2O)]n (H3MOPhIDC = 2-p-methoxyphenyl-1H-imidazole-4,5-dicarboxylic acid) (1), [Zn(μ2-HMOPhIDC)(2,2′-bipy)]n (2,2′-bipy = 2,2′-bipyridine) (2), [Co(μ2-HMOPhIDC)(2,2′-bipy)]n (3), [Co(μ2-HMOPhIDC)(phen)]n (phen = 1,10-phenanthroline) (4), [Cd1.5(μ2-H2MOPhIDC)(μ3-HMOPhIDC)(H2O)]n (5) and {[Co1.5(μ2-H2MOPhIDC)(μ3-HMOPhIDC)(py)]·2H2O}n (py = pyridine) (6) have been successfully synthesized under hydrothermal conditions, and characterized by means of elemental analyses, IR and single-crystal X-ray diffraction. The organic ligand H3MOPhIDC can be singly deprotonated or doubly deprotonated, and coordinate to metal ions in various modes. Polymers 1–4 display an infinite polymeric chain structure connected by μ2-HMOPhIDC2− ligands, but show different crystal packing fashions. Polymers 5 and 6 exhibit two-dimensional sheet structures built from double-stranded chains. The thermal properties of polymers 1–6 and luminescence properties of 2 and 5 have been determined. Also, the magnetic properties of polymers 1, 3, 4 and 6 have been investigated.