Syntheses, Structures And Properties Of Rare Earth And Alkaline Earth Complexes Based On Multipodal Carboxylate Ligands

It is well-known that carboxylate ligands play an important role in coordination supramolecular chemistry because of their diverse coordination modes and stronger bonding ability. In recent years, the most hot subjects of intensively current research in the cross domain of coordination chemistry, supramolecular chemistry and materials chemistry have focused on building novel functional coordination supramolecular compounds through metal-ligand coordination and intermolecular interactions (such as hydrogen bonds,π-πstacking, halogen-halogen interactions et al.) between carboxylate ligands and ions. Rare earth ions possess the special 4f electron configuration are responsible for the unique chemical and physical properties of the rare earth complexes. So they are applied widely in the optical, electrical, magnetic fields, and so on. Especially, design and synthesis of highly luminescent rare earth complexes with multi-carboxylate ligands are of great interest at present, due to outstanding optical properties of the rare earth complexes such as narrow emitting bands, long-lived, high quantum efficiency. Meanwhile, alkaline earth ions are a group of inorganic ions with larger ionic radius, higher coordination number, and the building of complexes with specific properties is attracted much attention. New types of multipodal carboxylate ligands were synthesized and their rare earth and alkaline earth complexes were also synthesized and characterized, and the solid-state luminescent, magnetic, gas adsorption properties of the complexes were systemic researched.The dissertation includes the following four chapters:Chapter 1:A brief review of investigation progress of rare earth and alkaline earth complexes with building by carboxylate ligands were summarized.Chapter 2:Tripodal carboxylate ligands H3LⅠ～H3LⅣhave been designed and synthesized from 2-amino-2-(hydroxymethyl)propane-1,3-diol and fifteen rare earth complexes with H3LⅠ～H3LⅣhave been synthesized and characterized by means of elementary analysis, IR, TGA and X-ray single-crystal diffraction. These results indicated that the cage-like dimeric coordination structures were formed by the rare earth ions with the three arms of the ligands. The structures of the complexes were not influenced obviously by changing fluorophore or introducing substituent of ligands.Chapter 3:The photoluminescence properties of corresponding europium and terbium complexes were investigated. The influences of different ligands on the luminescence properties were studied in detail. The results showed that:ⅰ) It is available for tuning singlet and triplet energy level of tripodal carboxylate ligands by changing fluorophore or introducing different substituents at 4- or 5-position of the benzene ring;ⅱ) H3LⅠexhibit a good antenna effect with respect to the Eu (Ⅲ) ion which is a result of altering the ligand triplet state,ⅲ) H3LⅡ～H3LⅣare suitable as sensitizers for Tb(Ⅲ) due to the triplet levels of ligands. On the basis of the magnetic studies, the weak anti-ferromagnetic coupling between the gadolinium(Ⅲ) ions can be observed in the complex based on H3LⅠ.Chapter 4:Multipodal carboxylate ligands H2LⅤ～H3LⅥhave been designed and synthesized from 2-amino-2-(hydroxymethyl)propane-1,3-diol and 2-amino-2-methylpropane-1,3-diolthe and three alkaline earth complexes have been synthesized and characterized by means of elementary analysis, IR, TGA, PXRD and X-ray single-crystal diffraction. These results indicated that the number of arms of ligands have great influence on the structures of the alkaline earth complexes. In addition, the luminescent properties and the gas adsorption behavior of the alkaline earth complexes were studied.The ligands involved in the dissertation are listed as follow: H3LⅠ:1,1,1-tris [(2'-caboxy-3'-naphoxy) methyl]-p-toluene sulfonyl aminomethane H3LⅡ:1,1,1-tris [(2'-caboxyphenoxy-5'-methyloxy) methyl]-p-toluene sulfonyl aminomethane H3LⅢ:1,1,1-tris [(2'-caboxyphenoxy-4'-methyl) methyl]-p-toluene sulfonyl aminomethane H3LⅣ:1,1,1-tris [(2'-caboxyphenoxy-5'-bromine) methyl]-p-toluene sulfonyl aminomethane H2LⅤ:1,1,-di [(4'-caboxyphenoxy) methyl]-1'-methyl-p-toluene sulfonyl aminomethane H3LⅥ:1,1,1-tris [(2'-caboxyphenoxy) methyl]-p-toluene sulfonyl aminomethane...