Synthesis, Structure And Properties Of Coordination Polymers Constructed From Cyclopentane Carboxylic Acid And Semi-rigid Asymmetric Carboxylic Acid

Nowadays, a great deal of coordination polymers based on multitopic organic spacers and metal ions have been self-assemblied. And the structures and properties possessed mainly depend on the natures of the organic bridging ligands and metal centers. Because of abundant conformations and more coordination topics, many coordination polymers based on cycloalkylcarboxylic acids with multi carboxylate groups have been synthesized up to now, which are proven having excellent properties in molecular optics, magnetism and catalysis. In the beginning of this dissertation, cyclopentanetetracarboxylic acid (cis,cis,cis,cis-1,2,3,4-cyclopentanetetracarboxylic acid) has been chosen as researching object. In order to investigate the conformation-transfer behaviors, four new "brick-wall"-shaped coordination polymers have been hydrothermal synthesized, which are structural characterized by Single-Crystal X-Ray Diffraction analyses, Fourier Transform Infrared Sppectroscopy (FTIR), Elemental Analyses (EA), Thermogravimetric Analysis (TGA) and Powder X-Ray Diffraction analyses (PXRD). Besides, the properties are also studied (for example, thermostabilities, fluorescence characteristic and magnetism). The conformation of the cyclopentanetetracarboxylate ligand in the initial reactant and the final coordination polymers are also investigated. The result shows that the temperature plays the most important role during the conformation-transfer when constructing coordination polymers with organic ligands of various conformations.In addition to that mentioned above, coordination polymers with V-shaped semi-rigid symmetry carboxylate ligands have attracted quite attentions because the backbone of the spacers could twist around the center non-metallic atoms, which are proven to have many excellent properties in luminescence, magnetism, catalysis and absorption. Compared to the symmetry ones, the reports about complexes based upon ?-shaped semi-rigid asymmetry ligands are a little rare, probably because the asymmetry characters of the backbones, which make the final structures unpredictable. Coordination polymers constructed with the semi-rigid asymmetry carboxylate ligands have been proven to have charming architectures and excellent luminescence and magnetic properties. In the following researches of this thesis, two semi-rigid asymmetry carboxylate ligands with oxygen atom as the center non-metallic atoms,3-(3'-carboxyphenoxy)phthalic acid (3-H3cpta) and3-(4'-carboxyphenoxy)phthalic acid (4-H3cpta) are chosen to constructed coordination polymers. The coordinated behaviors and the influence factors during the assembling CPs are also studied in the further researches: 1. Two semi-rigid asymmetric carboxylic acids are used as the main ligands at the same time, and different types of N-donor ligands are also chosen, such as pillar-bridge linked N-donor ligands and chelate ligands as the auxiliary ligands. After assembling with different metals, six coordination polymers with diverse structures were synthesized, which have different dimensionalities, topological structures and properties:{Cd3(2,2'-bpy)2(3-cpta)2·H2O}n (5)?{Cd(bpa)0.5(3-cpta)·[NH2(CH3)2]}n (6)?{Mn3(2,2'-bpy)2(3-cpta)2·H2O}n (7)?{Mn(bpa)0.5(3-cpta)(H2O)2·2H2O}n (8)?{Zn3(1,10-phen)2(3-cpta)2(H2O)2·2H2O}n(9)?{Zn3(dpa)2(4-cpta)2}(10). Complex5and7are the fist type of chiral layer structure with this type ligands; Complex6is a anionic2D layer structure, which is neutralized by the lattice dimethylamine cation; Complex8and Complex6are synthesized under the same reaction condition but different metal salts, different from Complex6, Complex8is a3D framework. Complex9and10are synthesized with the same auxiliary ligand and solvent but different carboxylate position, which make the final structures quite different. The result of the research shows that solvents, metal ions and positions of the substituents all have the important influences on the CPs with this type organic ligand. Besides, the luminescence properties of Complex5,6,9,10and magnetic properties of Complex7and8are also studied.2. In order to study the influence factors during the process of coordination polymers construction aspects,3-(4'-carboxyphenoxy)phthalic acid (4-H3cpta) and Co(II) ion are synthesized with bpe/bpa under hydro/solvothermal reactions, and three new coordination polymers11-13are obtained:{Co3(cpta)2(bpe)3(H2O)4}n (11){Co2(?2-H2O)(?3-OH)(Hcpta)(bpe)(H2O)·3(DMF)3(H2O)}n (12)?{Co3(cpta)2(bpa)4}n (13). After the study about the structures of the single crystals, it is shown that solvents play the main effect to the final structures. While the natures of the auxiliary ligands play the important role on the final properties of the complexes. In addition, the supermolecular forces between framework and guest molecules in Complex12(hydrogen bonds and van der waals force) and interaction forces between molecules make the whole structure more stable. The magnetic properties among the three complexes are also studied.