Based On,2,4,5 Cyclohexane - 1-4 Carboxylic Acid Coordination Polymer Building And Its Performance Study

Metal-organic frameworks (MOFs) complexes have attracted considerable interest lately because of their potential applications in a variety of areas, including catalysis, ion exchange, sensors, shape-selective adsorption, gas storage, photochemistry, and materials with magnetic properties. Over the past years, plenty of MOFs with variable dimensionality and different coordination styles have been designed and synthesized. Recently, the synthesis and investigation of coordination polymers with flexible multi-dentate ligands, which are capable of producing diversified new systems with different dimensionality and coordination styles when adding new cooperative ligands, have gradually caught the special attentions of researchers. In this work, we are interested in two aspects of the formation of coordination polymers that consist of metal and flexible ligands:(1) synthetic conditions under which the polymers can be formed and the conditions that the conformation of flexible ligands can be exclusively converted to the sole form; and (2) how different kind of metals influence the conformation of ligands and the structural construction of the complexes. We select cyclohexane-1,2,4,5-tetracarboxylic acid as building blocks to construct coordination polymers with selected transition/lanthanide metal ions and auxiliary ligands guided by assembly principle of coordination polymer crystal engineering. We have synthesized16coordination polymers. They are listed as follows:[Zn4(CTAⅠ)(μ3-OH)(μ2-OH)3(H2O)2]n·2n(H2O)(1),[Zn2(CTAⅡ)(H2O)3]n (2),[Cd2(CTAⅠ)(bipy)1.5(H2O)2]n·3n(H2O)(3),[Mn2(CTAⅠ)(bipy)1.5(H2O)2]n·3n(H2O)(4),[Co2(CTAⅠ)(bpe)(H2O)2]n·6n(H2O)(5),[Ln4(CTAⅠ)3(H2O)10]n·9nH2O(Ln=6, Eu;7, Gd;8, Nd;9, Dy),[Co2(CTAⅠ)(N3)2(H2O)]n (10),[Co5(CTAⅠ)2(phen)2(OH)2(H2O)4]n·4n(H2O)(11),[Co6(CTAⅠ)2(bpy)2(OH)4(H2O)2]n·6n(H2O)(12),[Co4(CTAⅠ)2(bipy)3(H2O)6]n·2n(H2O)(13),[Co4(CTAⅠ)2(bpa)2(H2O)8]n·8n(H2O)(14) and [Co(H2CTAⅠ)(bpp)n (15). The final coordination polymers have been characterized by XPRD analysis, X-ray single crystal diffraction, elemental analyses, IR spectra, thermal analysis. The potential photoluminescent, magnetic and adsorption properties have also been tested and investigated. The structure of complexes1-15have been described in detail and compared with each other. We have researched the conformation selection and coordination modes of flexible ligand H4CTA in coordination polymers. The effect of auxiliary ligands in structures of the final polymers has been also discussed.