| In recent years, the rational design and synthesis of novel metal-organic coordination polymers based on carboxylate ligand have attracted considerable attention. Carboxylate compounds have a good many coordination modes, and benzoate primarily has five coordination modes, such as: 1) unidentate, 2) chelating bidentate, 3) bidentate, 4) bridging unidentate, 5) chelating/bridging bidentate. The supramolecular complexes have interesting topological structure as well as potential applications as catalysis, smart opto-electronic, medicine, magnetic and porous materials.Making use of ligands and complexation ions with particular conformation can gain supramolecular complexes of anticipative structure and properties through self-assemble process. However, there are many factors affecting molecular self-assembly, such as the structure of ligands, complexation construction of mental ions, solution, hydrogen bond and the interaction of π-π. Therefore, the ligand is the most important factor.In my thesis, o-nitrobenzoate and 1,10-phenanthroline were selected as mixed ligands to form functional complexes, and some supramolecular complexes were synthesized using o-nitrobenzoate, nicotinamide and transition metal ions. What's more, bridged ligands, such as pyridine-4-carboxylic, l,2-di(4-pyridyl)ethylene, 4-sulfophthalic, were selected to perform varied self-assembly. Volatilization and hydrothermal methods were used to grow single crystals of the complexes, and the influence of different reaction condition was investigated.This paper consists of three sections except the introduction as follows:1. Chapter 1: Five complexes were synthesized using mixed ligands of o-nitrobenzoate, 1,10-phenanthroline and o-nitrobenzoate, nicotinamide respectively through self-assembly process. The complex [Zn(phen)(o-nitrobenzoic)2(H2O)] (2) is a mononuclear crystal, while complex [Cu(o-nitrobenzoic)2(phen)] (1) is dinuclear structure. Complex [Cu(o-nitrobenzoic)2(nicotinamide)2]-2H2O (3) exhibits a 1D chainstructure, and complexes of [Co(o-nitrobenzoic)2(nicotinamide)2(H2O)2]-2H2O (4) and [Cd(o-nitrobenzoic)2(nicotinamide)2(H2O)2]-2H2O (5) are both two-dimensional supramolecular networks through hydrogen bonds. Compaired with the complexes of (4) and (5), complex (3) has the same ligands as them but has different coordination environment around the metal ion. So, they display unidentical structure.2. Chapter 2: A one-dimensional saw-tooth shaped coordination polymer [Zn(dpe)(o-nitrobenzoic)2]n (6) was synthesized with o-nitrobenzoate, l,2-di(4-pyridyl)ethylene and Zn(Ac)2·2H2O. A novel three-mensional polymer [Pb(pyridine-4-carboxylic)2]n (7) was synthesized with pyridine-4-carboxylic, nicotinamide and Pb(NO3)2. The novel two-dimensional heterometallic polymer {[Cu(en)2]3[Mn(NCS)6]}(NCS)2(8) was synthesized with significant structure. To the best of our knowledge, the complex (8) is the unique [Mn(NCS)6]4- link up three distinct building blocks of [Cu(enh]2+ through SCN- bridges. And the complex may exhibit interesting ferromagnetic coupling between adjacent Mn and Cu ions.3. Chapter 3: Two novel isostrutural polymers {[M(phen)(4-sulfophthalic)(2H2O)] ·2H2O}n (M=Dy, Er) were synthesized with 1,10-phenanthroline and 4-sulfophthalic diammonium as bridged ligand. Mental ions are octocoordinated and two carboxylates exhibit unidentate and chelating bidentate coordination modes respectively. Three groups in the benzene of the ligand are coordinated with different mental ions, and the ligand acts as a bridge. Furthermore, three-dimensional novel supramolecular frameworks were constructed by hydrogen bonds and the π-π interaction between 1,10-phenanthroline in the complexes of (9) and (10).These complexes were characterized by IR, NMR, elemental analysis, TG, single-crystal X-ray crystallography and fluorescence spectra. |
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