Five new coordination polymers based on a semi-rigid dicarboxylic acid and versatile N-donor ligands: synthesis, characterization and properties

Abstract

Based on a semi-rigid dicarboxylic acid and N-donor ligands with versatile conformations, five new coordination polymers, namely, [Zn(pdda)(bpy)] (1), [Ni(pdda)(bib)]·H2O (2), [Ni(pdda)(bpp)] (3), [Cd2(pdda)2(bit)(H2O)2] (4) and [Mn4(pdda)4(phen)2]·H2O (5) (H2pdda = 4,4′-(1,3-phenylenedioxy)dibenzoic acid, bpy = 2,2′-bipyridine, bib = 1,4-bis(imidazole)butane, bpp = 1,3-bis(4-pyridyl)propane, bit = 1,4-bis(imidazol-1-ylmethyl)benzene, phen = 1,10-phenanthroline), have been synthesized under hydrothermal conditions. Their structures have been characterized by single-crystal X-ray diffraction analysis, elemental analysis, IR spectroscopy and thermogravimetric analysis. Compound 1 shows the interweaving of single helical chains. Compound 2 displays a polycatenane framework with the entanglement of (4,4) layers. Compound 3 exhibits a mutual incorporation of two (4,4) layers. Compound 4 is also a (4,4) layer structure which can be split into interesting double helixes. Compound 5 features a 3D framework of NbO topology. Their photochemical and magnetic properties were measured.