多金属氧簇超分子体系：分子识别、诱导手性及手性调控

发布时间：2018-03-21 02:43

本文选题：手性多金属氧簇　切入点：手性传递　出处：《吉林大学》2017年博士论文　论文类型：学位论文

【摘要】：随着多金属氧簇化学的发展,手性多金属氧簇因其独特的手性化学性质可用于分子识别,不对称催化,手性光学变色材料等领域而引起人们的广泛关注。多金属氧簇的手性性质可通过簇合物自身结构不对称性获得,但其手性结构极易消旋导致手性稳定性较差。在晶体与组装体中结构单元的不对称堆积可得到手性结构,但不易控制。通过共价与非共价修饰实现多金属氧簇的诱导手性具有较好的稳定性与可控性,成为手性多金属氧簇体系的研究热点之一。本文以多金属氧簇诱导手性为切入点,通过多组分超分子体系的设计实现多金属氧簇的诱导手性,调节体系中的超分子作用力实现可控的诱导手性。进一步利用电化学方法对多金属氧簇实现可控的氧化还原,构筑电致变色的多金属氧簇手性杂多蓝开关,同时多电子还原态下的手性杂多蓝现象也第一次被发现。最后,通过控制多金属氧簇与环糊精之间的距离实现其诱导手性的反转。工作内容主要实现三方面的研究进展:1.通过偶氮苯衍生物有机共价修饰Anderson型多金属氧簇获得具有双超分子位点的杂化物,利用杂化物的静电与主客体作用位点与阳离子、环糊精结合实现三组分超分子体系的构筑。环糊精内腔手性可传递给偶氮基,偶氮基的诱导手性可再次传递至阳离子,实现了超分子识别与手性的传递。通过改变体系温度与离子强度实现对超分子作用力的调控得到可控的诱导手性。2.利用客体阳离子实现对环糊精和多金属氧簇的超分子结合,使多金属氧簇获得诱导手性。通过电化学调控多金属氧簇的氧化还原状态,在还原态时产生手性杂多蓝,氧化过程中随着杂多蓝的消失诱导手性也随之消失,首次实现电致变色手性杂多蓝开关。3.在高浓度环糊精的溶液体系中,多金属氧簇作为客体与环糊精直接结合产生诱导手性。通过调控环糊精与多金属氧簇之间的结合距离,第一次实现多金属氧簇诱导手性的反转。水相中多金属氧簇的诱导及可控手性对于手性簇合物的构筑具有重要意义。超分子诱导手性与多金属氧簇的结合不仅为可控手性提供了新的方法与思路,同时也将扩宽了簇合物手性功能在水相中的应用,推动手性多金属氧簇在绿色化学中的发展。
[Abstract]:With the development of polyoxometallic cluster chemistry, chiral polyoxometalates can be used for molecular recognition and asymmetric catalysis because of their unique chiral chemical properties. The chiral properties of polyoxometallic clusters can be obtained by the asymmetric structure of the clusters. However, the chiral structure is easily racemic and leads to poor chiral stability. The chiral structure can be obtained by asymmetric stacking of structural units in crystals and assemblies. But it is not easy to control. The induced chirality of polyoxometallic clusters by covalent and non-covalent modification has good stability and controllability, and has become one of the research hotspots in chiral polyoxometallic clusters. The chiral inducement of polyoxometallic clusters was realized by the design of multicomponent supramolecular system, and the controllable chirality was achieved by adjusting the supramolecular forces in the system. Furthermore, the controllable redox of polyoxometallic clusters was realized by electrochemical method. An electrochromic polyoxometallic cluster chiral heteropoly blue switch was constructed, and the chiral heteropoly blue phenomenon in the multi-electron reduction state was first discovered. The induced chiral inversion is achieved by controlling the distance between polyoxometalates and cyclodextrins. The main work is to achieve three aspects of research progress: 1. The preparation of Anderson polyoxometalates by organic covalent modification of azobenzene derivatives. Hybrids with double supramolecular sites, Cyclodextrin was combined with cyclodextrin to construct a three-component supramolecular system. The chirality of cyclodextrin could be transferred to the azo group, and the induced chirality of the azo group could be transferred to the cation again. The supramolecular recognition and chiral transfer were realized. By changing the temperature and ionic strength of the system to regulate the supramolecular force, the induced chiral force was controlled. 2. The supramolecular binding of cyclodextrin and polyoxometallic clusters was achieved by using guest cations. By electrochemically regulating the redox state of polyoxometalates, the chiral heteropoly blue is produced in the reduced state, and the chirality disappears with the disappearance of the heteropoly blue in the oxidation process. It is the first time to realize electrochromic chiral heteropoly blue switch. In the solution system with high concentration of cyclodextrin, polyoxometalates directly bind with cyclodextrin as guest to produce induced chirality. By regulating the binding distance between cyclodextrin and polyoxometallic cluster, For the first time, the chiral inversion induced by polyoxometallic clusters is realized. The induction and controllable chirality of polyoxometalates in aqueous phase are of great significance for the construction of chiral clusters. The combination of supramolecular induced chiral clusters with polyoxometalates is not only. Controllable chirality provides new methods and ideas, At the same time, the application of chiral polyoxometalates in water phase will be broadened, which will promote the development of chiral polyoxometalates in green chemistry.
【学位授予单位】：吉林大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：O641.3

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