三甲基膦支持的钴配合物对醛基C-H键和Si-H键活化的探究以及催化性质的探索

发布时间：2018-01-05 07:42

本文关键词：三甲基膦支持的钴配合物对醛基C-H键和Si-H键活化的探究以及催化性质的探索　出处：《山东大学》2017年硕士论文　论文类型：学位论文

【摘要】：有机膦配体对于过渡金属配合物有着非常强的稳定作用。在金属有机化学中,人们通常通过改变膦配体的性质来调节金属配合物的电子密度,从而改变配合物的性质。三甲基膦作为一种膦配体,具有体积小、配位性强、光谱信号易识别等优点,从而常被应用于金属有机配合物的构建。碳氢键广泛地存在于有机物中。在一定条件下切断碳氢键并将其定向地转化为其他基团可以提高有机合成过程中的高效性和原子经济性,有效简化和缩短反应步骤。与传统方法相比,过渡金属化合物在这方面具有独特的应用潜力。醛基中的碳氢键较为活泼,不但容易与过渡金属化合物发生反应从而实现碳氢键的活化,还有可能发生进一步的脱羰反应。α,β不饱和醛是一种特殊的醛,由于其结构中共轭的碳碳双键和碳氧双键都可以被活化,其与过渡金属化合物的反应产物会具有一些独特的性质。目前关于这方面的研究主要集中在钌、铑、钼、铱等贵金属,而对于廉价金属钴的研究较少。其低廉的价格、独特的性质以及环境友好的特性在有机合成应用中非常有潜力。近年来,硅基过渡金属配合物也吸引越来越多研究者的目光,而通过过渡金属配合物活化硅氢键从而发生氧化加成反应是制备此类化合物的重要方法之一。通过对硅基金属配合物的研究可以帮助人们更加深刻理解过渡金属参与的催化反应的机理。其中,利用NSiN型的硅氮烷配体与过渡金属配合物反应来合成此类化合物是一种新的合成途径,且硅氮烷本身更是在材料化学、有机合成等领域展现出广阔的应用前景。本论文主要分为以下三个部分:第一部分利用三甲基膦支持的CoMe(PMe3)4,CoCl(PMe3)3和Co(PMe3)4与三种肉桂醛的衍生物反应,得到三种η4型的钴化合物1-3和五种η2型的钴化合物4-8。化合物1-8的结构经过IR和NMR的完整表征,其中化合物1-4和8的结构进一步通过单晶X射线衍射分析证实。第二部分利用三甲基膦支持的CoCl(PMe3)3和CoMe(PMe3)4分别与两种硅氮烷发生反应,得到了两种硅氮烷配位的钴化合物9-10。化合物10的结构经过IR和NMR的表征,且进一步通过单晶X射线衍射分析证实。第三部分以化合物10做催化剂以三乙氧基硅烷作为氢源催化醛酮的硅氢化反应,但是该反应对于底物的适用性较差,有待进一步的改进。
[Abstract]:Organic phosphine ligands are very stable to transition metal complexes. In organometallic chemistry, the electron density of metal complexes is regulated by changing the properties of phosphine ligands. As a phosphine ligand, trimethyl phosphine has the advantages of small volume, strong coordination, easy recognition of spectral signals, and so on. Thus it is often used in the construction of organometallic complexes. Hydrocarbon bonds are widely present in organic compounds. Cutting off the hydrocarbon bonds and converting them to other groups can improve the efficiency of organic synthesis under certain conditions. Sex and atomic economics. Effective simplification and shortening of reaction steps. Transition metal compounds have unique potential applications in this area compared with traditional methods. Carbo-hydrogen bonds in the aldehyde group are active. It is not only easy to react with transition metal compounds to realize the activation of hydrocarbon bond, but also possible to decarbonylation further. 伪, 尾 unsaturated aldehydes are special aldehydes. Because the conjugated carbon-carbon double bonds and carbon-oxygen double bonds in their structures can be activated, the products of their reactions with transition metal compounds will have some unique properties. At present, the research on this aspect is mainly focused on ruthenium and rhodium. Molybdenum, iridium and other precious metals, but less research on low-cost cobalt. Its low price, unique properties and environmentally friendly properties in organic synthesis has great potential in recent years. Silicon-based transition metal complexes have attracted more and more researchers' attention. It is one of the important methods to prepare the transition metal complexes by activating the hydrosilyl bond through the transition metal complexes. The study of the silicon-based metal complexes can help people to understand the transition metals more deeply. Participate in the mechanism of catalytic reaction. It is a new way to synthesize NSiN type silane ligand and transition metal complex, and silane itself is in the material chemistry. Organic synthesis and other fields show broad application prospects. This paper is divided into the following three parts: the first part is CoMe(PMe3)4 supported by trimethyl phosphine. CoCl(PMe3)3 and Co(PMe3)4 reacted with three derivatives of cinnamaldehyde. Three kinds of 畏 4 cobalt compounds 1-3 and five 畏 2 cobalt compounds 4-8 were obtained. The structures of compounds 1-8 were characterized by IR and NMR. The structures of compounds 1-4 and 8 were further confirmed by single crystal X-ray diffraction. In the second part, CoCl(PMe3)3 and CoMePMe3 supported by trimethyl phosphine were used. 4reacted with two kinds of silane respectively. Two kinds of cobalt compounds coordinated with silane were obtained. The structure of compound 10 was characterized by IR and NMR. The third part uses compound 10 as catalyst to catalyze the hydrosilylation of aldehydes and ketones with triethoxy silane as the hydrogen source, but this reaction is not suitable for the substrate. Further improvements are needed.
【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O641.4;O643.36

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