Low-coordinate Compounds of Main Group Elements and their application in the activation of H2, CO, CO2 and NH3

主族元素低配位化合物及其在H2、CO、CO2和NH3活化中的应用

• 批准号: 435224417
• 负责人: Dr. Alexander Hinz
• 金额: --
• 依托单位: Institut für Anorganische Chemie (aoc)
• 依托单位国家: 德国
• 项目类别: Independent Junior Research Groups
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/435224417?language=en
• 关键词: Low; coordinate; Compounds; Main; Group

The controllable transformation of small molecules such as H2, CO, CO2 and NH3 has been a relevant research area for both transition metal and main group chemists. To achieve this, in general the synthesis of particularly reactive compounds is necessary. For their stabilisation three methods have been employed: steric shielding, tuning of electronic properties by the substituents and the coordination of additional Lewis acids or bases. In previous projects we developed sterically encumbering monodentate monoanionic Subsituents for this purpose. Based on these substituents we propose the utilisation of monocoordinate atoms in molecules for the synthesis of reactive main group element compounds. Further development of sterically demanding substituents is an integral part of all three subprojects. The first project is focused on the chemistry of heavy tetrylenes. Halotetrylenes bearing bulky carbazolyl substituents will be studied with respect to halogen abstraction and reduction, thereby allowing access to building blocks of the general composition [R–E14]+/0/–. These offer various further options for derivatisation by both metathesis reactions and the stoichiometric reaction with small molecules, allowing systematic access to tetrylenes with tunable electronic properties. These tetrylenes could be used in the transformation of small molecules as well. The second projects is aimed at the investigation of a new class of multiple bonds. Heavy analogs of nitriles and isonitriles with heavy elements of group 14 are hitherto unknown, but they promise to possess interesting reactivity. For heavy nitrile analogs there is a balance of electronic influences that should enable reactivity between nitrene and nitride. In isonitrile analogs the group 14 element is monocoordinated; consequently there are various possible reaction pathways with small molecule substrates. Following the syntheses of achetypical multiple bond syntheses and a thorough analysis of bonding in them, their reactivity towards small molecules and metal complexes should be studied. The third project targets the synthesis of carbazolyl complexes in which Lewis acidity dominates the reactivity. Structural motifs such as monocoordinate earth alkaline and earth metal compounds should be generated, as they already should be strong Lewis acids that react with a variety of small molecules. Furthermore, corresponding hydride complexes could be obtained. Both the cationic and the hydride compounds are going to be studied initially in stoichiometric, then in catalytic transformations of relevant substrates in reactions such as hydrosilylations, hydroborations and hydrogenations.

H_2、CO、CO_2、NH_3等小分子的可控转化一直是过渡金属和主族化学家研究的热点。要做到这一点，一般来说，合成特别活性的化合物是必要的。对于它们的稳定，采用了三种方法：空间屏蔽，通过取代基调节电子性质，以及配位额外的Lewis酸或碱。在以前的项目中，我们为此目的开发了空间封闭的单齿单阴离子取代物。基于这些取代基，我们建议利用分子中的单配位原子来合成活性主族元素化合物。进一步开发空间要求很高的取代基是所有三个子项目不可或缺的一部分。第一个项目的重点是重四烯的化学。将研究含有大量咔唑取代基的卤代四丙烯对卤素的提取和还原，从而允许获得一般组成[R-E14]+/0/-的构建块。这为通过歧化反应和与小分子的化学计量反应进行衍生化提供了各种进一步的选择，允许系统地获得具有可调电子性质的四丙烯。这些四苯类化合物也可用于小分子的转化。第二个项目是针对一种新类别的多重债券进行调查。到目前为止，含有第14族重元素的腈和异腈的重类似物是未知的，但它们有望具有有趣的反应性。对于重丁腈类似物，存在电子影响的平衡，这应该使氮化物和氮化物之间的反应成为可能。在异腈类似物中，第14族元素是单配位的；因此，与小分子底物的反应有多种可能的途径。在合成了非典型的多键化合物并对其中的键进行了深入的分析之后，应该研究它们对小分子和金属络合物的反应性。第三个项目的目标是合成咔唑络合物，在该络合物中，Lewis酸性控制着反应性。应该生成单配位的土碱和土金属化合物等结构基元，因为它们应该是与各种小分子反应的强Lewis酸。此外，还可以得到相应的氢化物络合物。阳离子化合物和氢化物化合物都将首先在化学计量学中进行研究，然后在硅氢化、硼氢化和氢化等反应中研究相关底物的催化转化。