Electron-rich phosphines, switchable lewis (super)acids and cooperative metal complexes: new prospects for the activation of CO2, N2, H2, N2O and SO2 and their utilization as synthetic building blocks

富电子膦、可转换路易斯（超）酸和协同金属配合物：CO2、N2、H2、N2O和SO2活化及其作为合成构件的利用的新前景

• 批准号: 324098411
• 负责人: Professor Dr. Fabian Dielmann
• 金额: --
• 依托单位: Institut für Allgemeine, Anorganische und Theoretische Chemie
• 依托单位国家: 德国
• 项目类别: Independent Junior Research Groups
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/324098411?language=en
• 关键词: Electron; rich; phosphines; switchable; lewis

The activation of small molecules such as CO2, N2, H2, N2O and SO2 for energy-efficient chemical transformations is a key challenge of current research. The present project is concerned with the development of new methods for the utilization of these molecules as synthetic building blocks and for their transformation into fuels for chemical energy storage. In our previous studies we showed that very electron-rich phosphines PR3 were obtained by attaching strong donor substituents R (R = imidazolin-2-ylidenamino) at the phosphorus atom. The resulting phosphines are powerful ligands in homogeneous catalysis and they form reversible CO2 adducts with low energy barriers. Based on these results, the synthesis of new donor substituents R with optimized properties (photoswitchability, water stability, variable steric and electronic properties) is proposed in the present project. These R substituents constitute the common synthetic building blocks in the following three subprojects: In subproject 1 the activation of CO2 and SO2 with uncharged strong Lewis bases is proposed targeting towards the Lewis base-catalyzed functionalization of CO2 and the controlled release of SO from SO2 under mild conditions. In this respect, phosphines, phosphine oxides and guanidine bases with variable steric and electronic properties will be developed, and their ability to form CO2 and SO2 adducts will be investigated. Subproject 2 is concerned with the activation of H2, N2O, CO2 and N2 using novel Lewis (super)acids with switchable Lewis acidity. In this context, sterically protected, trigonal planar phosphorus and boron cations will be prepared. These Lewis acids comprise the feature that their Lewis acidity can be increased by irradiation with UV light or by protonation. The goal is to activate N2O, CO2 and SO2 by complexation to the Lewis acids and to enables their subsequent reaction with weakly nucleophilic substrates such as alkenes, alkines or aromatic compounds. Liberation of the reaction products from the Lewis acid shall be accomplished by switching of the Lewis acidity. In subproject 3 the cooperative activation of N2 and H2 at Cu, Au, Ru and Fe complexes is proposed. Specific ligand design and the generation of polymetallic structures shall allow for the isolation of N2 complexes with the coinage metals. A second focus lies on the catalytic hydrogenation of N2 to form NH3 using Ru and Fe pincer complexes.

活化CO2、N2、H2、N2 O和SO2等小分子进行节能化学转化是当前研究的一个关键挑战。本项目涉及开发利用这些分子作为合成构件和将其转化为化学能量储存燃料的新方法。在我们以前的研究中，我们表明，非常富电子的膦PR 3是通过在磷原子上连接强供体取代基R（R =咪唑啉-2-亚基氨基）获得的。所得膦在均相催化中是强有力的配体，并且它们形成具有低能量势垒的可逆CO2加合物。基于这些结果，本项目提出了新的供体取代基R的合成与优化的性能（光开关，水稳定性，可变的空间和电子性能）。这些R取代基构成了以下三个子项目中常见的合成结构单元：在子项目1中，提出了用不带电荷的强刘易斯碱活化CO2和SO2，目标是在温和条件下刘易斯碱催化CO2的官能化和SO从SO2的受控释放。在这方面，膦，氧化膦和胍碱与可变的空间和电子性能将被开发，并将研究它们形成CO2和SO2加合物的能力。子项目2涉及使用具有可切换的刘易斯酸性的新型刘易斯（超级）酸活化H2、N2 O、CO2和N2。在这种情况下，将制备空间保护的三角平面磷和硼阳离子。这些刘易斯酸包括其刘易斯酸性可通过用UV光照射或通过质子化而增加的特征。目标是通过与刘易斯酸络合来活化N2 O、CO2和SO2，并使它们能够与弱亲核底物如烯烃、炔或芳族化合物进行后续反应。反应产物从刘易斯酸中的释放应通过切换刘易斯酸度来完成。在子项目3中，提出了N2和H2在Cu、Au、Ru和Fe络合物上的协同活化。特定的配体设计和多金属结构的产生应允许与钴金属的N2络合物的分离。第二个焦点在于使用Ru和Fe钳形络合物催化N2氢化形成NH3。

项目成果

Reversible CO2 fixation by N-heterocyclic imines forming water-stable zwitterionic nitrogen-base–CO2 adducts

• DOI: 10.1039/c8gc02952k
• 发表时间: 2019-02
• 期刊: Green Chemistry
• 影响因子: 9.8
• 作者: Lukas F. B. Wilm;T. Eder;Christian Mück‐Lichtenfeld;Paul Mehlmann;Marius A. Wünsche;Florenz Buß;Fabian Dielmann

Pyridinylidenaminophosphines: Facile Access to Highly Electron‐Rich Phosphines

• DOI: 10.1002/chem.201904621
• 发表时间: 2019-12
• 期刊: Chemistry (Weinheim an Der Bergstrasse, Germany)
• 作者: Philipp Rotering;Lukas F. B. Wilm;Janina A. Werra;Fabian Dielmann

Isolation, characterization and reactivity of three-coordinate phosphorus dications isoelectronic to alanes and silylium cations

• DOI: 10.1038/s41557-019-0348-0
• 发表时间: 2019-12-01
• 期刊: NATURE CHEMISTRY
• 影响因子: 21.8
• 作者: Mehlmann, Paul;Witteler, Tim;Dielmann, Fabian
• 通讯作者: Dielmann, Fabian