【作者】 马天亮；

【导师】 刘云凌； 徐家宁；

【作者基本信息】 吉林大学 ， 无机化学， 2012， 博士

【摘要】 随着科技和社会的不断进步，设计和开发新材料已经成为当前化学领域最为热门的研究课题。金属有机配位聚合物材料作为化学领域一个重要的分支，在其蓬勃发展的短短二十年间，取得了许多喜人的成果，并在吸附、分离、催化、传感、光、电、磁等诸多领域显示出极为广阔的应用前景。设计和合成特定的结构是这类材料研究中的重要环节，而配体的选择对于这一环节则至关重要。通过对有机配体进行取代基修饰能够得到一系列具有结构新颖、功能独特的金属有机配位聚合物，这方面的研究近年来正受到材料化学家的广泛关注。本文中，我们通过对刚性配体4,5-咪唑二羧酸的2-位进行取代基修饰，得到了甲基，乙基，羟甲基，吡啶基和苯甲酸取代的五种咪唑羧酸衍生物，并以此作为有机配体来进行金属有机配位聚合物的合成，获得了九种结构共十五个化合物，并对它们进行了相关性质的表征。研究工作主要集中在以下三个方面：1.在混合溶剂热体系下，以2-甲基-4,5-咪唑二羧酸作为配体，草酸作为辅助配体，成功地制备了一系列稀土金属有机配位聚合物，|（H₂O）₄|[Ln₂（H₂O）₃（HMImDC）₂（OX）]（Ln=Sm（1）, Eu（2）, Gd（3）, Pr（4）, Nd（5））。这五个化合物是晶体学同构的，该结构是由两种zigzag链（之字形链）组成的二维层通过金属与配体的二聚体单元进一步连接而形成的三维骨架，并且在a轴方向存在着孔径为8.9×3.8（?）的一维孔道。该系列化合物的结构特色是金属与2-甲基-4,5-咪唑二羧酸交替连接形成了围绕Ln-OX zigzag链旋转的螺旋链状结构，这在已报道的金属有机配位聚合物中是比较少见的；相同手性的螺旋链并排连接形成手性的层状结构，手性对应的层彼此交替相连进而形成内消旋的三维骨架结构。化合物1-5可以简化为4-节点（3,5）-连接的新颖拓扑结构，而且这也是第一例以2-甲基-4,5-咪唑二羧酸为配体的稀土金属有机配合物。通过固体荧光和变温磁化率的测定，化合物2在紫外光的激发下发出较强的红光，显示了较好的荧光性质。化合物3则显示出较弱的反铁磁性质。该系列化合物具有较好的热稳定性，骨架能稳定到350oC，可作为潜在的光学或磁学材料。2.选择烷基链稍长的2-乙基-4,5-咪唑二羧酸作为有机配体，分别以2-苯基咪唑和三乙烯二胺作为辅助配体，在混合溶剂热体系下合成了两个分别具有一维链状和二维层状结构的金属有机配位聚合物，[Zn（HEImDC）（PhIm）]（6）和|DMA|[Zn₂（HEImDC）₂（dabco）]（7）；以草酸作为辅助配体，在水热体系下合成了三个三维的稀土金属有机配位聚合物，|H₂O|[Ln₂（H₂O）2（HEImDC）（OX）₂]（Ln=Sm（8）, Eu（9）, Gd（10））。化合物6和7的结构中都存在着金属中心与配体形成的三角双锥型结构单元[ZnN₃O₂]，这些结构单元通过2-乙基-4,5-咪唑二羧酸相连形成一维zigzag链状结构；化合物6中的zigzag链通过辅助配体2-苯基咪唑与相邻链上羧基之间的氢键作用进一步形成了具有类蜂窝状的超分子层状结构，化合物7中的zigzag链则通过三乙烯二胺分子彼此桥连而形成以-AB-的方式堆积的层状结构。化合物8-10是晶体学同构的，其结构是由金属四核簇相互连接构成的一维链通过辅助配体草酸在两个方向进一步相连而形成三维网络骨架，并且可以简化为2-节点（4,4）-连接新颖拓扑学结构。另外，该系列化合物的结构中存在着两组手性对应的螺旋链状结构，其中一组螺旋链是由-Ln1-OX-Ln2-HEImDC-Ln1-OX-Ln1-连接而形成的，并且两条手性对应的链之间通过Ln1-OX-Ln1相互连接；另一组是由-Ln2-OX-Ln1-HEImDC-Ln₂-HEImDC-Ln₂-构成的，两条手性对应的链之间通过Ln₂离子彼此相连。化合物9在紫外光的激发下发出红光，展现了较好的光学性质。3.为了对咪唑羧酸衍生物类配体进行系统性的研究，我们将取代基进行进一步拓展，选用目前研究较少的2-羟甲基-4,5-咪唑二羧酸，2-（4-吡啶基）-4,5-咪唑二羧酸和2-（4-苯甲酸）-4,5-咪唑二羧酸作为配体成功地制备了五个新颖的配位聚合物，|DMF|[Zn₂（H₂OMImDC）₂（4,4’-bipy）]（11），Zn3（H₂O）₂（HOMImDC）₂（Im）₂（12），|DMF||H₂O|[Zn₂Mn_1.5（H₂O）₂（HOMImDC）₂（Tz）]（13），Ni（DMF）₂（HPyImDC）（14）和Cd（H₂BCImDC）（15）。化合物11-13都是以2-羟甲基-4,5-咪唑二羧酸作为配体，分别以4,4’-联吡啶、咪唑和1,2,4-三氮唑作为辅助配体来进行合成的。在化合物11中，[ZnN₃O₂]结构单元与2-羟甲基-4,5-咪唑二羧酸以及4,4-联吡啶配体形成两种六员环的结构单元，这些六员环之间通过共边连接进一步形成一个具有一维六边形孔道的层状化合物。化合物12是锌离子与2-羟甲基-4,5-咪唑二羧酸和咪唑混合配体共同构筑的具有bto拓扑学结构的手性三维金属有机配位聚合物，其结构中存在着由两条左手螺旋的手性链并列缠绕而成的具有单一右手手性的螺旋管状通道，这在手性结构的配位聚合物中是不多见的；并且每条螺旋通道周围存在着两组共六条单一右手螺旋的链状结构。化合物13是以2-羟甲基-4,5-咪唑二羧酸作为配体，1,2,4-三氮唑作为辅助配体，通过引入Zn和Mn两种金属离子共同构筑的三维金属有机配位聚合物，并且该化合物展现出较好的反铁磁性质。化合物14选用带有含氮取代基的2-（4-吡啶基）-4,5-咪唑二羧酸作为配体，形成了一个具有零维四边形结构的金属有机配位聚合物，并且四边形与四边形之间通过氢键连接形成二维超分子结构。化合物15则选用含羧基取代基的2-（4-苯甲酸）-4,5-咪唑二羧酸作为配体，构筑了一个具有二维层状结构的金属有机配位聚合物，层与层之间通过氢键连接进一步形成三维超分子结构。本文较为系统地研究了2-位上不同取代基的咪唑羧酸衍生物配体在合成金属有机配位聚合物的过程中的影响，选用过渡金属和稀土金属作为金属源制备了一系列具有光学、磁学和手性结构等性质的多功能晶体材料。并且将适当的辅助配体引入到合成体系，从而实现了骨架结构从零维到三维的可调控性。这些都为设计和合成多功能的金属有机配位聚合物提供了很多有价值的数据和信息。更多还原

【Abstract】 With the continuous advancement of technology and society, designing andexploiting new materials has become the most popular research topic in the fieldof chemistry. Metal-organic coordination polymers, as a very important branch inthe field of materials chemistry, has achieved many gratifying results andexhibited very broad potential applications in adsorption, separation, catalysis,sensors, luminescence, optoelectronics and magnetism during the two boomingdecades. The design and synthesis of specific structures is an important part ofsuch materials, in which it is crucial for the choice of ligands. In recent years,substituent modification on the organic ligands, as a effective way to construct aseries of metal-organic coordination polymers with novel structures and uniquefeatures, has attracted great attention of materials chemists. In this paper, weadopted five derivatives of the rigid ligands4,5-imidazole dicarboxylic acid, inwhich the hydrogen on2-position has been replaced by methyl, ethyl,hydroxymethyl, pyridyl and benzoic acid respectively, as ligands to guide thesynthesis of metal organic coordination polymers. Eventually, nine kinds ofstructure, total of fifteen compounds have been prepared and characterized, andall the results are mainly reflected in the following three aspects:1. A series of lanthanide-organic coordination polymers,|（H₂O）₄|[Ln₂（H₂O）₃（HMImDC）₂（OX）]（Ln=Sm （1）, Eu （2）, Gd （3）, Pr （4）, Nd （5）, H3MImDC=2-methyl-4,5-imidazoledicarboxylic acid, OX=oxalic acid）, have beensuccessfully synthesized under solvothermal conditions by employing2-methyl-4,5-imidazoledicarboxylic acid and oxalate as mixed organic ligands.Compounds1-5are isostructural and exhibit novel3D architectures which constructed by layers consisted of two type of zigzag chains and dimmersconsisted of lanthanides and [HMImDC]^2-ligands, in addition, there are openchannels of8.9×3.8along a axis. The structural featuers of compound1-5arethat lanthanides linked by [HMImDC]^2-ligands alternately to form a helical chainaround the zigzag chain of Ln-OX, which is rare in the metal-organic coordinationpolymers reported. The same chiral helices are arranged in parallel forming achiral layer, and the enantiomers of chiral layers connect with each otheralternately leading to the formation of3D structure which is racemic. Compounds1-5can be simplified to a4-nodal （3,5）-net, which is a new topological structure,and they are the first lanthanide-organic coordination polymers based onH₃MImDC ligand. Furthermore, compound2exhibits strong red luminescenceemission depending on the characteristic of Eu³⁺ions and compound3showsweak antiferromagnetic interactions by magnetic property investigation. All thecompounds can be stabilized up to350oC and may be used as a potential opticalor magnetic material.2. We take2-ethyl-4,5-imidazole dicarboxylic acid （H₃EImDC） with a longeralkyl chain as organic ligand,2-phenyl imidazole and1,4-Diazabicyclo[2.2.2]octane （dabco） as ancillary ligands, solvothermallysynthesized two1-D chain and2-D layered metal-organic coordination polymers,[Zn（HEImDC）（PhIm）]（6） and|DMA|Zn₂（HEImDC）₂（dabco）]（7）, respectively;and oxalic acid as another auxiliary ligand hydrothermally synthesized three3-Dlanthanide-organic coordination polymers,|H₂O|[Ln2（H₂O）₂（HEImDC）（OX）₂]（Ln=Sm （8）, Eu （9）, Gd （10））. The structure of compounds6and7both consist of[ZnN₃O₂] build units constructed by metal center and H₃EImDC ligands, whichare further connected by H₃EImDC to form a1-D zigzag chain structure. Incompound6, the adjacent zigzag chains connect with each other throughhydrogen-bonding interactions between2-phenyl-imidazoles and carboxylates togenerate a honeycomb-layered supramolecular structure, and compound7has aanalogous honeycomb-layered structure constructed by zigzag chains and dabcomolecules which described by an-AB-sequence along [101] direction. Compounds8-10are crystallography isomorphic and can be described as1Dchains consisted of lanthanide quad-core clusters connect with each other in twodirections through oxalate ancillary ligands forming3D architectures with2-nodal（4,4）-net. In addition, compounds8-10are corresponding to two sets ofopposite chiral helical chains. One set is formed by the connection of-Ln1-OX-Ln2-HEImDC-Ln1-OX-Ln1-, and two enantiomers with helicalcharacters link each other by Ln1-OX-Ln1units; the other formed by-Ln2-OX-Ln1-HEImDC-Ln2-HEImDC-Ln2-and the enantiomers shared withLn2ions. Furthermore, compound9emits intense red luminescence under UVexcitation which exhibit good luminescence properties.3. In order to systematically study the derivatives of4,5-imidazoledicarboxylic acid, we obtain three new ligands with extended substituents:2-（hydroxymethyl）-4,5-imidazoledicarboxylic acid （H4OMImDC）,2-（4-pyridyl）-4,5-imidazoledicarboxylic acid （H₃PyImDC） and2-（4-benzoicacid）-4,5-imidazoledicarboxylic acid （H4BCImDC）, and take them as bridgingligands successfully preparing five novel metal-organic coordination polymers,|DMF|[Zn₂（H₂OMImDC）₂（4,4’-bipy）]（11）, Zn3（H₂O）₂（HOMImDC）₂（Im）₂（12）,|DMF||H₂O|[Zn₂Mn1.5（H₂O）₂（HOMImDC）₂（Tz）]（13）, Ni（DMF）₂（HPyImDC）（14）and Cd（H2BCImDC）（15）. Compounds11-13use H4OMImDC as the ligands,4,4’-bipyridine, imidazole （Im）, and1,2,4–triazole （Tz） as auxiliary ligands,respectively. Compound11is a layered structure constructed from two types ofsix-membered metallocycles, with1-D hexagonal channel along c axis.Compound12is a3-D metal-organic coordination polymer with bto topologyconstructed from zinc ions, H4OMImDC and Im mixed-ligands, which has a rareright-handed chiral spiral tubular channel winded by two left-handed helices, aswell as two sets, total six of right-hand helical chains arranged alternately aroundthe tubular channel. Compound13is based on H4OMImDC as a main ligand, Tzas an auxiliary ligand, through the introduction of Zn²⁺and Mn²⁺ions together tobuild a3-D coordination polymer, and it exhibits good antiferromagneticinteractions. Compounds14uses H₃PyImDC as ligand to form a0-D quadrilateral structure, which connects with the neighbors via hydrogen-bonding interactions toform a2-D supramolecular structure; compound15is a2-D layered structurebased on H4BCImDC, with the hydrogen-bonding interactions between the layers,it can be realized as a3-D supramolecular structure.In summary, we systematically discuss the impacts of the different2-positionsubstituents in4,5-imidazoledicarboxylic acid derivatives on the synthesis ofmetal organic coordination polymers, and successfully prepare a series oftransition metal and lanthanide organic crystal materials with multi-functions suchas luminescence, magnetism and chirality. Furthermore, through the introductionof appropriate ancillary ligands into the synthetic system, the structures of somecompounds can be transformed from0-D to3-D. This work will provide a lot ofvaluable data and information for the design and synthesis of multifunctionalmetal-organic coordination polymers.更多还原