Anderson-Evans型多金属氧簇的有机修饰及构型转化研究

发布时间：2018-02-01 01:53

本文关键词： 多金属氧簇 Anderson-Evans 有机共价修饰 triol配体　出处：《吉林大学》2017年博士论文　论文类型：学位论文

【摘要】：多金属氧簇是由氧桥联前过渡金属形成的多核簇合物,在光化学,催化,磁性及医药领域均有广泛的应用。为丰富多金属氧簇的化学结构,拓展簇的功能化应用,便需要对多金属氧簇进行有机修饰,从而获得多金属氧簇有机-无机杂化复合物。在本论文中,我们将主要研究多金属氧簇的有机共价修饰。以盘状的Anderson-Evans型多金属氧簇作为研究对象,其中心杂原子周围的六个羟基可以全部或部分的被三羟基配体取代,形成有机-无机杂化物。这种方法具有合成简便,易于连接功能基团,产率高等优点,因而被广泛采用。但是对于此类反应中,三羟基配体修饰的类型、影响因素及反应机理等方面的研究还比较少。我们以此作为出发点,开展了以下几个方面的研究工作:(1)选择二价铜为中心杂原子,首次制备得到了三羟基配体修饰Anderson-Evans型多金属氧簇的双边半错位结构,同时通过控制溶液的酸碱环境,实现了不同结构类型之间的转变;(2)利用具有可变价态的钴为中心原子,得到了四种三羟基配体修饰Anderson-Evans型多金属氧簇的结构类型,发现了在空气中二价钴到三价钴的原位氧化及其伴随着修饰类型的改变,进一步的研究表明,通过控制反应条件,氧化过程可以加速,也可以被抑制。(3)通过控制加入反应物的比例,成功制备了一系列三羟基配体修饰的Anderson-Evans型簇反应中间体{M2Mo6}(M=Cu2+、Co2+、Ni2+和Zn2+)型化合物。中间体继续加入钼源即可将其转化为相应的Anderson-Evans型多金属氧簇。以含有二价铜的化合物为例,详细研究了不同环境条件对修饰类型的影响。通过对三羟基配体修饰的铜和钴中心Anderson-Evans型多金属氧簇的研究,成功获得了新颖的双边半错位修饰的簇结构,发现了酸碱环境对修饰类型的影响,实现了多种有机配体在多金属氧簇上的共修饰,并通过控制反应条件成功制备了一类可能的反应中间体。本论文的研究工作为Anderson-Evans型多金属氧簇的修饰提供大量的实例,所获得的理论知识对后续簇的修饰结构的研究具有一定的指导意义。
[Abstract]:Polyoxometallic clusters are polynuclear clusters formed by transition metals before oxygen bridging. They are widely used in photochemistry, catalysis, magnetism and medicine. They are rich in the chemical structure of polyoxometallic clusters. To expand the functional application of the cluster, it is necessary to modify the polymetallic oxygen cluster organically, so as to obtain the organic-inorganic hybrid complex of the polyoxometallic cluster. We will mainly study the organic covalent modification of polyoxometallic clusters, and take the discoid Anderson-Evans polyoxometallic clusters as the object of study. The six hydroxyl groups around the central heteroatom can be completely or partially replaced by trihydroxyl ligands to form organic-inorganic hybrids. This method has the advantages of simple synthesis, easy connection of functional groups and high yield. Therefore, it is widely used. However, there are few studies on the type of trihydroxyl ligand modification, influencing factors and reaction mechanism in this kind of reaction. We take this as our starting point. The following research work has been carried out: 1) selecting divalent copper as the central heteratomic atom. Trihydroxyl ligand modified Anderson-Evans polyoxometallic clusters were prepared for the first time, and the two-sided semi-dislocation structure was obtained by controlling the acid-base environment of the solution. The transformation between different structure types is realized. Using cobalt with variable valence as the central atom, four kinds of trihydroxyl ligand modified Anderson-Evans polyoxometallic clusters were obtained. The in-situ oxidation of cobalt divalent to trivalent cobalt in air and the change of modification type have been found. Further studies show that the oxidation process can be accelerated by controlling the reaction conditions. It can also be inhibited by controlling the proportion of reactants added. A series of trihydroxy-ligand modified intermediate {M _ 2Mo _ 6} M _ 2Mo _ 2 / Co _ 2 for Anderson-Evans cluster reaction have been successfully prepared. Ni2 and Zn2) compounds. The intermediates can be transformed into corresponding Anderson-Evans polyoxometallic clusters by adding molybdenum source. Take the compound containing divalent copper as an example. The effects of different environmental conditions on the modification types were studied in detail. The Anderson-Evans polyoxometallic clusters of copper and cobalt centers modified by trihydroxyl ligands were studied. A novel two-sided semi-dislocation modified cluster structure was successfully obtained, and the effect of acid-base environment on the modification type was found, and the comodification of various organic ligands on polymetallic oxygen clusters was realized. A class of possible reaction intermediates were successfully prepared by controlling the reaction conditions. This paper provides a large number of examples for the modification of Anderson-Evans polyoxometallic clusters. The theoretical knowledge obtained has certain guiding significance for the study of the modification structure of subsequent clusters.
【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】：O641.4

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