【作者】 李玉庆；

【导师】 黄晓春；

【作者基本信息】 汕头大学 ， 无机化学， 2010， 硕士

【摘要】 在溶剂热条件下,构筑具有新颖结构的功能配位聚合物一直是配位化学研究的热点之一;对具有特定结构的功能配合物在化学与物理性质上进行进一步的深入研究则是另一热点。本论文的主要工作是合成了两种咪唑衍生物配体,也就是2-（2-吡啶）-苯并咪唑和2-（2-吡啶）-（4,5）-咪唑二羧酸配体,用它们在溶剂热条件下制备了一些结构新颖的二价金属锌及镉的配合物,并对这些配合物的荧光性质以及其中两种可实现单相转化的配合物的机理进行了深入研究。本文共分为三章:第一章介绍了本论文研究背景,重点介绍了超分子配位聚合物所涵盖的广度;其次,配合物光致发光的理论基础概念;同时对主客体化学中配合物到配合物转化体系进行了简单介绍。最后针对咪唑类配体的研究现状,进一步阐述了本论文研究目的和意义。第二章介绍了本论文所采用的2-（2-吡啶）-苯并咪唑配体的合成方法,及基于2-（2-吡啶）-苯并咪唑配体（L1）上咪唑环的氮原子去质子化情况,定向自组装合成了一系列配合物[Ni（HL1）2Cl2]·2H₂O （1）、CuⅠCuⅡ（HL1）（L1）Cl2 （2）、[Co（L1）₃]·6H₂O （3）、Co（L1）₃（H₂O） （4）。在以上寡聚单核结构中,进一步引入第二配体间苯二酸（H₂ip）混配得到配合物[Cd₂（L₁）₂（Hip）₂（H₂O）₂]_n·nH₂O （5）、[Cd₂（L₁）₂（Hip）₂]_n （6）,并对其中配合物5到配合物6由于热力学控制的单向转化进行了深入研究,我们对配合物进行了一系列的实验与测定,包括热重分析（TGA）,示差扫描量热分析（DSC）, X-射线粉末衍射（PXRD）,变温X-射线粉末衍射（T-PXRD）等。并通过用乙二醇回流加热配合物5的方法,最终实现了配合物5向6的转化,但可惜的是,很难实现配合物6向5的逆转化。第三章介绍了本论文所采用的2-（2-吡啶）-（4,5）-咪唑二羧酸配体的合成方法,及基于2-（2-吡啶）-（4,5）-咪唑二羧酸（H₃L2）定向自组装合成了一系列二价金属锌和镉的配合物[Cd（H₂L₂）₂H₂O]·H₂O （7）、[Zn （H₂L₂）₂H₂O]·H₂O （8）、[Cd₂（HL₂）₂（H₂O）]_n （9）、[Cd₂（HL₂）₂（H₂O）]_n （10）、[Cd（HL2）]_n （11）,其中配合物7和8是寡聚同构配合物;配合物9,10,11是三个超分子异构体。最后对其荧光性质进行了深入的研究与探讨。第四章简单总结了这篇论文的工作,并对得到的数据结果展开讨论,以及围绕所得到二价金属锌和镉的配合物其前景应用的展望。更多还原

【Abstract】 Controlling the self-assembly of metal–organic frameworks （MOFs） is currently considered as one of the most active areas in coordination and supramolecular chemistry due to their intriguing crystal architectures, amazing topology structures and potential applications as optoelectronic, catalytic as well as separation materials. In this work, two imidazole derivatives, 2-（2’-pyridyl）-benzimidazole （HL1） and 2-pyridyl-imidazole-4, 5-dicarboxylic acid （H₃L2） were used as ligands to react with Zn（II） and Cd（II） under hydrothermal conditions, and a series of complexes have been synthesized. Moreover, crystal-to-crystal transformation was discussed with temperature controlled. Also, potential properties toward three supramolecular isomers （complex 9, 10, 11） have been investigated. The thesis is divided into four chapters:In the first chapter, around the research background, the concepts of both crystal engineering and supramoleculor chemistry were introduced in details; Also, of metal complexes the photoluminescence mechanism was clearly demonstrated; Moreover, it was still illuminated that single-crystal-to-single-crystal transformation around host-guest chemistry. Finally, the significance of this work based on imidazole-related coordination polymers was completely explained.In the second chapter, based on 2-（2’-pyridyl）-benzimidazole （HL1） ligand, trying to deprotonate the hydrogen atom of imidazole ring, a series of compounds have been self-assembled and synthesized as following: [Ni（HL1）2Cl2]·2H₂O （1）,CuⅠCuⅡ（HL1）（L1）Cl2 （2）, [Co（L1）₃]·6H₂O （3）,Co（L1）₃（H₂O） （4）; All of the above four coordination compounds behave zero-dimensional structural character no matter HL1 deprotonated or not. In order to assemble multi-dimensional complexes, isophthalic acid （H₂ip, a second ligand ） was introduced, then two novel cadmium coordination polymers of mixed ligands with both 2-（2’-pyridyl）-benzimidazole （HL1） and isophthalic acid （H₂ip）: [Cd₂（L₁）₂（Hip）₂（H₂O）₂]_n·nH₂O （5） and [Cd₂（L1）2（ip）₂]_n （6）, have been synthesized by hydrothermal method with the same stoichiometric ratio of metal and ligands under different reaction temperatures respectively at 120¹40°C and 160-180°C. The different structures of the compounds indicate that the temperature plays a significant role in the construction of the coordination polymers. Interestingly, 5 can be further converted to 6, via heating and also stirring 5 in a flask around 160°C for three days with ethylene glycol as solvent, which has been demonstrated by UV & PXRD. Moreover, thermal gravimetric analysis （TGA） and photoluminescence of 5 and 6 were discussed in details.In the third chapter, based on 2-pyridyl-imidazole-4, 5-dicarboxylic acid （H₃L2） ligand, a series of Zn（II）, Cd（II） complexes have been synthesized under hydrothermal conditions as followed: [Cd（H₂L₂）₂H₂O]·H₂O （7）, [Zn （H₂L₂）₂H₂O]·H₂O （8）, [Cd₂（HL₂）₂（H₂O）]_n （9）, [Cd₂（HL₂）₂（H₂O）]_n （10）, and [Cd（HL2）]_n （11）. It is noteworthy that 9, 10 and 11 are supramolecular isomers, which were produced under stoichiometry control as well as pH control. Moreover, thermal gravimetric analysis （TGA） and photoluminescence of complex 8, 9 and 10 were discussed in details.The fourth chapter, it mainly concisely summarize the content of the whole thesis; Also, for the results obtained in this thesis and future application around those Zn（II）, Cd（II） complexes have further discussed.更多还原