Aluminum and gallium metallacycles as element/carbon-based ambiphiles for small molecule activation

该项目的目的是建立新颖的，迄今为止仅零星研究的分子内Al/C-和Ga/C-基两性亲和物。除了文献中已知的系统之外，还开发了金属环双亲性试剂，它们应该能够作为“隐藏的”受挫刘易斯对（FLPs）反应，也可以与难以激活的小分子反应，例如NH3，在N-H键切割下，理想情况下是可逆的。这种反应行为对于目前描述的FLPs是未知的，甚至对于过渡金属配合物也是具有挑战性的。特别是考虑到氮氢活化氨作为一种易于获得和原子经济的氮源在氢胺化反应中的应用，这是非常有趣的。在前期工作的基础上，本课题的重点是对金属环Al/ c双亲分子的定向微调、扩展和总体建立，以及通过生成新的Ga/ c双亲分子对基于小环体系的隐藏FLPs概念的持续扩展。对小分子的键激活和可能的催化转化的系统研究伴随着量子化学计算来描述结构、键和反应性。

The aim of this project is to establish novel and so far only sporadically studied intramolecular Al/C- and Ga/C-based ambiphiles. Beyond the systems known from the literature, metallacyclic ambiphiles are developed, which should be able to react as "hidden" Frustrated Lewis Pairs (FLPs), also with small molecules that are difficult to activate, such as NH3, under N-H bond cleavage, ideally reversible. Such reaction behavior is unknown for the FLPs described so far and challenging even for transition metal complexes. Especially in view of the use of N-H-activated ammonia as a readily available and atom-economical nitrogen source in hydroamination, this is of great interest. Building on the results of our preliminary work, the key points of the research project are the targeted fine-tuning, extension and general establishment of metallacyclic Al/C-ambiphiles as well as the consistent extension of the concept of hidden FLPs based on small ring systems by the generation of novel Ga/C-ambiphiles. Systematic studies on bond activation of small molecules and possible catalytic transformations are accompanied by quantum chemical calculations to describe structure, bonding and reactivity.