镍催化碳氮键的选择性官能团化

发布时间：2018-02-23 23:30

本文关键词： 镍硼化活化碳-氮健烯烃高化学选择性　出处：《南京大学》2017年博士论文　论文类型：学位论文

【摘要】：碳-氮键是最丰富的化学键之一,并且广泛存在于许多有机分子和生物大分子中。碳-氮键高的离解能和稳定性,使它们成为合成有机化学中最普遍的惰性有机化合物之一。毫无疑问,碳-氮键断裂仍然是一个具有挑战性的课题,并且将在未来的化学中引起极大的关注。由于易获得的含氮化合物能提供优异的氮源或碳源构建有用的分子,因此,过渡金属催化碳-氮键裂解已经成为一个研究热区。本课题组致力于发展惰性化学键的断裂活化,使其进行官能团化,并取得了一定进展。基于文献和实验研究基础,我的博士论文围绕碳-氮键断裂活化,且该转化具有优秀的化学选择性,官能团兼容性和高的转化效率。本论文的研究包括季铵盐碳-氮键的直接硼化,酰胺的脱羰硼化和脂肪酰胺的脱羰β-氢消除,如下:第一部分:建立一种温和的镍催化体系,使sp~2和sp~3碳-氮键直接断裂硼化。这高效的反应主要取决于适合的化学体系:催化剂Ni(COD)2,配体ICy·HCl和乙二醇单甲醚共溶剂。而且,这转化不仅具有较好的官能团兼容性,也能作为一种强大的有机合成方法。鉴于-NMe2基团及其羧酸前体在化学中的广泛应用,该方法提供了一种有意义的工具,使其成为有用的反应模块。由于这些优点,该反应应具有高的合成价值。第二部分:建立一种镍/氮杂卡宾催化体系,通过碳-氮键活化,使酰胺脱羰与B2nep2进行硼化。这转化不仅能兼容各种官能团,也能作为一种强大的酰胺硼化合成方法。鉴于酰胺及其羧酸前体在化学中的广泛应用,该方法提供了有用的工具,以使得它们能够作为有价值的结构单元。更重要的是,首次分离得到金属中间体(酰基镍复合物),并通过X衍射证实其结构。而且也观察到其脱羰过程。这些研究证实了酰胺碳-氮键断裂的关键机理过程。第三部分:酰胺和烯烃是具有可逆性的重要合成中间体,其在天然产物,药物和人造材料的构建中起关键作用。将高度稳定的脂肪族酰胺直接转化为烯烃是一项具有挑战性的任务。本课题组建立一种镍/氮杂卡宾催化体系,通过碳-氮和碳-碳键断裂活化,使脂肪酰胺脱羰消除形成各种烯烃。这种方法不仅克服了脂肪酰胺碳-氮键的活化,而且创新了一种独特的消除反应,称之为"retro-hydroamidocarbonylation"。这种化学转化不仅能兼容各种官能团,也能作为一种强大有机方法学,使脂肪酰胺转化为烯烃化合物。
[Abstract]:Carbon nitrogen bond is one of the most abundant chemical bonds, and widely exists in many organic molecules and biological macromolecules. The dissociation of carbon nitrogen bonds with high energy and stability, making them one of the most common inert organic compound in organic chemistry. There is no doubt that the carbon nitrogen bond rupture is still a a challenging task, and caused great concern in the future. Because of easily available chemical compounds containing nitrogen can provide excellent nitrogen or carbon source to construct useful molecules, therefore, transition metal catalyzed C-N bond cleavage has become a research hotspot. The activated fault research group is committed to the development of inertia the chemical bond, the functional groups, and some progress has been made. Based on literature and experimental research based on my PhD thesis on carbon nitrogen bond cleavage activation, and the conversion of chemical selectivity and excellent functional compatibility And high conversion efficiency. Direct boronation the research includes quaternary carbon nitrogen bond, decarbonylation of boron and fatty amide decarbonylation of hydride elimination, are as follows: the first part: the establishment of amide is a mild nickel catalyst system, the sp~2 and sp~3 direct fracture of boron carbon nitrogen bond. This high efficiency mainly depends on the chemical reaction system suitable for the catalyst Ni (COD) 2, ICy ligand - HCl and ethylene glycol monomethyl ether solvent. Moreover, this transformation not only has good functional compatibility, can also be used as a powerful method for organic synthesis. Given the wide application of -NMe2 group and its former carboxylic acid in chemistry, the method provides a useful tool to become useful reaction module. Because of these advantages, the reaction has high value of synthesis. The second part: the establishment of a nickel / aza CABBEEN catalyst system, the carbon nitrogen bond activation, the amide decarbonylation Boron and B2nep2. This transformation is not only compatible with various functional groups, and also can be used as a powerful method for synthesis of amide boride. Given the widely used amide and carboxylic acid precursor in chemistry, this method provides a useful tool, so that they can serve as a valuable structural unit is more important. For the first time, isolated metal intermediates (acyl nickel complex), and its structure was confirmed by X diffraction. And also observed the decarbonylation process. This study confirmed that the key mechanism of amide carbon nitrogen bond fracture. Third part: amide and olefins are important intermediates are reversible, in the natural construction products, drugs and artificial materials plays a key role. The highly stable aliphatic amide directly into olefins is a challenging task. This paper established a nickel / aza CABBEEN catalytic system, through carbon The activation of nitrogen and carbon carbon bond cleavage, the fatty amide decarbonylated eliminate the formation of various olefins. This method not only overcomes the activation of fatty acid amide carbon nitrogen bond, but also create a unique elimination reaction, called "retro-hydroamidocarbonylation". This conversion is not only compatible with various functional groups, and also can be used as a strong organic methodology, the fatty acid amide into alkenes.

【学位授予单位】：南京大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：O621.251

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