Syntheses And Properties Of Coordination Compounds Based On The Carboxylate Ligands With Crown Ether Group And Aromatic Carboxylate Ligands

Metal-organic coordination polymers constructed from metal ions and multifunctional organic ligands as an important class of solid-state materials have potential applications in gas-storage, photoelectron materials, magnetic materials and catalytic properties. The research of metal-organic coordination polymers has been attracted current attention in inorganic chemistry, organic chemistry, solid state chemistry, and materials chemistry. The metal component may confer useful optical electronic or magnetic properties, mechanical hardness, and thermal stability, while the organic component offers processability, a potential for structural diversification,and a range of polarizabilities. Therefore, the metal-organic coordination polymers can exhibit both characteristics of organic matter and properties of inorganic component.This thesis presents the synthesis and structural characterization of three organic carboxylic acid ligands with the crown ether functional group(H2L1(1), H4L2(2) and H2L3(3)) and describes the synthesis and crystal structures and physical properties of the metal-organic coordination polymers based on these organic carboxylate and other carboxylate ligands such as 1,4-benzenedicarboxylate and1,4-naphthalenedicarboxylate. This thesis has five chapters as following.Chapter 1: The introduction and overview of the metal-oganic coordination polymers is presented in this chapter. This chapter mainly focuses on the latest research progress of the metal-organic coordination polymers based on the organic carboxylic acid ligands with the functionalized crown ether group and other aromatic carboxylate ligands.Chapter 2: Three carboxylic acid organic ligands with the crown ether groups have been synthesized and structural characterized, namely H2L1(1), H4L2(2) and H2L(3), respectively. Much effort has been focused on the synthesis of the metal-organic coordination polymers based on these three organic ligands. However,only two compound can be characterized by the X-ray single-crystal diffraction,namely, {[Zn(bpy)(H2O)]4(DHBDC)}n(4) and Zn(1,10-phen)(DHBDC)(H2O)2(5)(bpy = 4,4’-bipyridyl, DHBDC = 2,3-dihydroxybenzene-1,4-dicarboxylic acid,1,10-phen = 1,10-phenanthroline), which revealed that both of the carboxylic ligand are hydrolyzed and in situ formation of the 2,3-dihydroxy-1,4-benzenedicarboxylate ligand. Moreover, compound(6) was also characterized by the X-ray single-crystal diffraction, but the diffraction of this compound is too weak to determinate the crystal structure. Therefore this compound was characterized by IR spectroscopy. Lastly, the study of the interaction between the crown ether groups of these three organic ligands and the sodium ion are also investigated.Chapter 3: Three novel lanthanide compounds, namely,{(EMIM)2[Sm2(BDC)3(H2-BDC)Cl2]}n(7) and {(EMIM)[Ln2(μ2-Cl)(BDC)3]}n(Ln= Eu(8) and Tb(9), H2-BDC = 1,4-benzenedicarboxylic acid, EMIM =1-ethyl-3-methylimidazolium) have been synthesized under ionothermal conditions.These compounds are consist of anionic 3D frameworks and extraframework charge-balancing specie of imidazolium [EMIM]+cations. Detailed photoluminescence studies show all compounds exhibit typical lanthanide luminescence emissions and the Eu(III) and Tb(III) luminescences are efficiently sensitized by the organic ligand.Chapter 4: A coordination polymer [Co4(μ2-H2O)2(1,4-ndc)4(dpp)2]n(10) with the 1, 4-naphthalenedicarboxylic acid(1,4-H2ndc) and 1, 3-di(4-pyridyl)propane(dpp)mixed ligands has been synthesized and structurally and magnetically characterized.The 3D coordination network of compound 10 is a rare 10-connected network of(36.434.53.62) topology based on the tetranuclear cobalt cluster nodes. Magnetic measurements on compound 10 indicate that there is a net antiferromagnetic coupling among the Co(II) ions.Chapter 5: The summary of the thesis is provided in this chapter.