【作者】 马琦；

【导师】 朱苗力； 卢丽萍；

【作者基本信息】 山西大学 ， 无机化学， 2010， 博士

【摘要】 近年来,配位聚合物晶体材料迅猛发展,已成为当前配位化学、材料化学和晶体工程的热点研究领域之一,这不仅是由于它们具有多种多样的拓扑结构,而且还因为它们在电化学、催化、离子交换、气体存储和磁性等方面有着潜在的应用。目前研究工作集中在运用晶体工程学原理,通过选取适当的金属离子和有机配体,合理利用配位键和超分子作用(氢键、π…π相互作用等)实现具有新颖拓扑结构配位聚合物的构筑。一般来说,配合物的自组装受各种因素的共同影响,如金属离子特殊的配位能力与构型、有机配体的特性、平衡离子的干扰、溶剂影响和反应条件等。其中,有机配体是构筑配位聚合物的关键因素,因此对配体的设计和研究备受关注。本论文选择了两种含N的杂环配体(1,10-邻菲咯啉-5,6-二酮,4-氨基-3,5-二甲基-1,2,4-三唑)及含两种N、O杂原子杂环羧酸(1H-1,2,4-三唑-3,5-二羧酸,2,6-吡啶二羧酸)配体,并对所形成配位聚合物的结构和性质进行了细致的研究。全文共分为五部分：一、简单介绍了配位聚合物的发展及组装,对配位聚合物按照配体的不同进行分类,总结了含氮配体(以4,4-联吡啶和1H-1,2,4-三唑为例)和含氧配体(以2,6-吡啶二羧酸为例)的成果,提出本课题的选题意义。二、设计并合成六个1,10-邻菲咯啉-5,6-二酮为配体的配合物,测试并解析了其晶体结构。化合物1为1D“之”字链,化合物2为1D分子螺旋链,化合物3-5分别为单核化合物,6是一个N的α-位C被羟基化的1,10-邻菲咯啉-5,6-二酮,详细研究了1-4的电化学、紫外和荧光及圆二色性质,有趣的是发现具有14号空间群晶体结构的化合物2的CD谱在固体中是惰性的,在乙腈溶液中也是惰性的,但是在DMSO溶液中有正的Cotton效应,通过电喷雾质谱和粉末X射线衍射研究确定样品中没有能够产生信号的其它物种,因此我们认为DMSO促使化合物2的两个对应异构体在溶液中受到不同的扭曲；晶体结构解析表明,1-3的金属离子虽然为同一族,但配位的本质却是完全不同,这主要是与金属离子的离子半径和晶体半径有关,部分工作发表于Crystal Growth & Design,2010,10,1706-1714。三、基于1H-1,2,4-三唑-3,5-二羧酸配体的多种可能的配位模式,提出了可能的配位模式的图例表示(?),设计合成了八个配位聚合物,对所形成的配位聚合物进行了红外、元素分析和晶体结构表征,聚合物7是一个由三核Mn结构单元构筑的1D链状结构,8是一维链状结构,两个聚合物都表现出反铁磁相互作用。聚合物9是2D(4,4)拓扑结构,10是一个单核配合物,11与8同构,也是一维链状结构,且配体的配位模式相同；在7-10四个化合物中,配体H3dctrz表现出不同的配位模式,分别为(?)(7),(?)(8),(?)(9),(?)(10)。在水热条件下合成三个聚合物12-14,聚合物12为二维结构,13和14为三维聚合物,晶体结构解析结果发现,水热条件下,出乎意料,1H-1,2,4-三唑-3,5-二羧酸配体不稳定,容易脱去两个羧基生成1H-1,2,4-三唑。本章部分工作已发表在Dalton Trans,2010,39,5877-5884.四、以4-氨基-3,5-二甲基-1,2,4-三唑、NaN3和KSCN为混合配体与过渡金属离子Mn(Ⅱ)、Co(Ⅱ)通过自组装合成了两个配位聚合物[Mn3(N3)6(admtrz)4]n(16)和[Co3(NCS)6(admtrz)4(H2O)2]·2H20(17)。16为三核Mn(Ⅱ)簇为建筑单元构筑的2D层状(4,4)拓扑结构,颇为有趣的是,在聚合物16中,N3-存在三种结合模式,分别为μ-1,1-N3-(EO),μ-1,3-N3-(EE)和端基N3-,1.8-300K变温磁化率测定与拟合分析发现,Mn2+离子间存在反铁磁相互作用。这个结构最有趣的特征是二维层沿着b轴方向表现出了一个波形,其周期为17.4668(?)。17为三核Co(Ⅱ)形成的簇合物,SCN采用EO和端基N配位模式,磁性研究表明该化合物金属离子之间也为反铁磁相互作用。两个配合物中,admtrz均采用μ-1,2-triazole桥连模式,这部分正在组织整理文章。五、选择2,6-吡啶二羧酸为配体,与稀土La(NO3)3和Ce(NO3)3及过渡金属混合金属离子反应得到了四个新的配位聚合物。化合物18为1D链状结构,其结构的主要特点是四核构筑单元通过μ-1,1-O桥连成为一维链状结构；19为2D层状,从结构上可以看成是沿a轴方向由{La(PDA)2}单元形成的1D链和由b轴方向由{AgLa(PDA)2}构筑单元形成的1D链形成的2D层状结构。化合物20和21是六核簇合物,两个六核簇合物是在相同的溶液中结晶出的不同结构。20是两个三核单元之间通过μ2-O桥连原子连接形成整个六核分子结构。21是两个三核亚结构单元通过μ1,3-COO羧基桥连模式连接成一个六核结构,这部分正在补充性质,组织整理文章。本论文较为详细地阐述了含氮杂环(1,10-邻菲咯啉-5,6-dione,2,6-吡啶二羧酸和1,2,4-三唑)金属有机配位聚合物的合成方法、结构特点及磁性等性质。通过研究结构与功能之间的关系,丰富了金属有机配位聚合物合成化学和结构化学研究内容,同时为该材料的定向合成和性质开发积累了有价值的科学数据。更多还原

【Abstract】 The research of coordination polymer(metal-organic frameworks,MOFs) remains one of the an extremely active fields of material chemistry, coordination chemistry and crystal chemistry in recent years. The construction of metal-organic frameworks is of great interest due to their intriguing network topologies and their potential applications as catalysts, ion exchange, gas storage, electrochemistry and magnetism. Crystal engineering based on organic linkers and metal centers with specific coordination geometries is an important approach in the preparation of coordination materials with desired functions. In addition to coordinative covalent bonding which is most important in constructing coordination polymer, hydrogen bonding,π-πstacking interaction and other weak intermolecular interactions have attracted considerable interest in the construction of supramolecular coordination framework. Generally speaking, the generation of self-assembling coordination architectures depends on the combined effect of several factors, such as:the coordination geometry of the metal ions, the feature of the organic ligands, the coordinated and/or non-coordinated counter ions, the solvent systems, the reaction conditions, and so on. Among these factors, beyond doubt, the ligand is one of the most important factors for fabricaing the structure of coordination polymer. Therefore, the application of well-designed ligands to control the assembly of molecular architectures has become a popular and rapidly growing discipline.In the thesis, we have adopted four ligands with N or O heteroatoms (1,10-phenroline-5,6-dione,4-amino-3,5-dimethyl-1,2,4-triazole,2,6-pyridine-dicarboxylic acid and 1H-1,2,4-triazole-3,5-dicarboxylic acid), The crystal structures and properties of these complexes have also been investigated.(ⅰ). Development and assembly of coordination polymers are concisely introduced, and classification of coordination polymers according to the different ligands(such as: 4,4-bipyridine, 1H-1,2,4-triazole and 2,6-pyridine-dicarboxylic acid) is summarized. And then, we introduce our research topic.(ⅱ). Six complexes were synthesized and characterized through the self-assembly of pdon ligand and d10 or d5 metal ions, compex 1 is a one-dimensional zigzag chain connected byμ-Cl bridge, complex 2 is a one-dimensional molecular helix chain bridged by doubleμ1,3-SCN bridge,3-5 are mononuclear complexes, in 6, we observed hydroxylation of pdon ligand. Electrochemistry, UV-vis, Fluorescent and CD properties of complexes 1-4 were in detail studied. Result indicates that the CD spectrum of complex 2 shows positive Cotton effect in the wavelength range of 200-360 nm in DMSO solution, while it was not found in acetonitrile solution. Complex 2 crystallized in P21/c space group with racemic mixtures with zero CD intensity in the solid state, powder XRD pattern of 2 shows phase purity. So we think that these positive Cotton effects may come from complex 2 with some degree of enantiomeric excess, the average degree of twisting between left-hand and right-hand helical forms. Although Zn2+, Cd2+, and Hg2+ are elements of the same group, their self-assembly behaviors were essentially different. The architectures may relate to crystal and ionic radii (A, C.N.6) of metal ions, Mn (0.81,0.67), Zn (0.88,0.74), Cd(1.09,0.95), and Hg (1.16,1.02). Part work has been published in Crystal Growth & Design,2010,10,1706-1714.(ⅲ). Based on colorful coordinaton modes of the 1H-1,2,4-triazole-3,5-dicarboxylic acid ligand, we proposed a pattern designator(Mhijknlm) to specify coordination modes of H3dctrz(Scheme 3.2). Eight polymers were successfully designed and synthesized by solution evaporation and hydrothermal technique, and characterized by IR, element analysis and single crystal X-ray diffraction. Complex 7 is a 1D chain consisting of trinuclear Mn2+ cluster basic units,8 and 9 being a 1D chain and a 2D (4,4) topology structure, repectively. Magnetic properties of two complexes 7 and 8 indicate that two polymers exhibit antiferromagnetic interaction between metal ions.10 is a mononuclear complex. Complexes 7-10 have different coordination modes 32001110 (7),21001001 (8),31011001(9), 10001001(10) respectively. Complexes 12-14 were hydrothermally synthesized. X-Ray diffraction analysis shows that H3dctrz ligand was unexpectedly decarboxylated under hydrothermal conditions. This part of work has been published in Dalton Trans,2010,39, 5877-5884.(iv). We adopted three kinds of bridging ligands (KSCN, NaN3,4-amino-3,5-dimethyl-1,2,4-triazole) with transition metal ions to synthesize two new complexes and studied their magnetic properties. The results show that two complexes exhibit antiferromagnetic interaction. Complex 16 is a 2D layer (4,4) topology structure consisting of trinuclear (Mn2+)3 building units. To our surprise, there are three kinds of coordination modes for N3- in the trinuclear building units respectively, namely μ-1,1-N3-(EO),μ-1,3-N3·(EE) and terminal N3-. The most interesting feature of this structure is that this two-dimensional layer represents a wave shape along b-axis direction. The period is ca.17.4668 A. Complex 17 is only a trinuclear structure, SCN- adoptedμ-1,1-SCN-(EO) and terminal N-coordination modes. In the two complexes structures, admtrz ligand adoptedμ-1,2-triazole bridging mode.(v). Four new complexes were synthesized by using 2,6-pyridine-dicarboxylic acid ligand, La(NO3)3, Ce(NO3)3 and transition metal ions. Complex 18 is a 1D linear structure and the main feature of its structure is to build tetranuclear units throughμ-1,1-O bridge with a one-dimensional chain structure.19 is a 2D layer structure consisting of 1D chain forming by La(PDA)2 units along a axis and 1D chain by [AgLa (μ-1,4-PDA)2] building units along b axis.20 and 21 are the two different crystal structures obtained in the same solution.20 is a hexanuclear clusters forming by the two trinuclear units bridged byμs-O atoms.21 is a six-core structure connected into sub-structure of two trinuclear units throughμ1,3-COO carboxyl-bridged mode.In this thesis, we in detail described synthesis, crystal structure, and properties containing N-hetercycle metal-organic coordination polymers. By studying the relationship between structure and function, our work not only enriched and developed synthesis chemistry and structural chemistry of metal organic coordination polymer, but also accumulated the valuable experimental data for the synthesis and property development of the materials.更多还原