Ambiphilic Phosphinines: a paradigm shift for aromatic phosphorus heterocycles?

在这项续订建议中，将继续进行非常成功的关于两亲性膦的化学项目。自1966年G. Märkl首次成功合成膦衍生物以来，这些吡啶的高级同源物的反应性、配位化学和应用都是由它们的电子（和部分立体）性质决定的：膦的特点是内在的弱亲核性和磷原子的碱性，因此它在芳香体系中的嵌入同时在供体原子上产生显著的亲电性。这种组合无疑会产生有趣的（后续的）化学反应，但另一方面也会阻止人们接触到典型的有机磷（III）化合物。在第一阶段的资助过程中，通过在磷杂环上引入合适的取代基来改变膦的亲核和亲电性质的许多最初设想的想法和概念显然可以非常成功地实现。结果的多样性也保证了第二阶段化学的非常多方面，因此，在这里，除了进一步研究功能化膦的基本性质和获得仍然未知的双氮杂酰基取代膦外，将主要针对（催化）键激活反应领域的应用。重点是下列目标：(i)二氮杂酰基取代膦碱及其后续化学反应；（ii）膦-硼烷/丙烯路易斯对的插入和环加成反应；（iii）与膦-硼烷/丙烯路易斯对的催化反应；（iv）与亲电膦的键激活反应；（五）亲电膦与碳烯和氟化物的反应。第一个筹资期的先前结果和初步工作保证在第二个项目阶段也能成功地执行计划的广泛研究。

In this continuation proposal, the very successful project on the chemistry of ambiphilic phosphinines is to be continued. Since the first successful synthesis of a phosphinine derivative by G. Märkl in 1966, the reactivity, coordination chemistry and application of these higher homologues of the pyridines have been determined by their electronic (and partly steric) properties: Phosphinines are characterised by an intrinsically weak nucleophilicity and basicity of the phosphorus atom, whereby its embedding in an aromatic system simultaneously gives rise to significant, electrophilic properties at the donor atom. This combination undoubtedly allows for interesting (follow-on) chemistry, but on the other hand also prohibits access to compounds typical for classical organophosphorus(III) compounds. In the course of the first funding phase, it became apparent that many of the originally postulated ideas and concepts for modifying the nucleophilic and electrophilic properties of phosphinines by introducing suitable substituents on the phosphorus heterocycle could be implemented very successfully. The diversity of the results promises a very multifaceted chemistry also in the second phase, whereby here, in addition to further research into the fundamental properties of functionalised phosphinines and access to still unknown diazaboryl-substituted phosphinines, applications in the field of (catalytic) bond activation reactions will be mainly targeted. The following goals are in focus: (i) diazaboryl-substituted phosphinines and their follow-up chemistry; (ii) insertion and cycloaddition reactions on phosphinine-borane/alane Lewis pairs; (iii) catalytic reactions with phosphinine-borane/alane Lewis pairs; (iv) bond activation reactions with electrophilic phosphinines; (v) reactions of electrophilic phosphinines with carbenes and fluorides. The previous results and preliminary work from the first funding period promise a successful implementation of the planned extensive studies also in the second project phase.