Ligand-Metal Electron Transfer Processes in Complexes of Late Transition Metals with Redoxactive Guanidine Ligands: Fundamental Understanding and Applications in Redox Catalysis

后过渡金属与氧化还原性胍配体配合物中的配体-金属电子转移过程：氧化还原催化的基本理解和应用

• 批准号: 404520422
• 负责人: Professor Dr. Hans-Jörg Himmel
• 金额: --
• 依托单位: Anorganisch-Chemisches Institut
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/404520422?language=en
• 关键词: Ligand; Metal; Electron; Transfer; Processes

Coordination compounds with redox-active ligands are currently intensively studied, due to the additional possibilities that arise from ligand redox-activity. A redox-active ligand could act as electron reservoir to enhance substrate activation in catalytic applications. Moreover, redox-active ligands often are present as radical ligands, and the increased spin density on the ligand leads to a special, ligand-centered reactivity. Finally, the properties (e.g. Lewis acidity) of a metal directly bound to a redox-active ligand change with the redox state of the redox-active ligand. My research group studies coordination compounds with redox-active guanidine ligands. These ligands could be devided into two classes, the Guanidino-Functionalized Aromatics (GFAs), consisting of two or more guanidino groups directly attached to an aromatic core, and the urea azines and related compounds, consisting of two guanidinyl groups (or related groups) that are directly connected to each other via an N-N bond. Both compound classes are of relevance for the planned studies. The project is composed of two sub-projects, TP1 and TP2. The directed stimulation of intramolecular electron-transfer processes by a variety of different stimulants is the main topic in TP1. In difference to the first funding period that concentrated on preferably small bis- and tetrakisguanidine ligands, redox-active oligoguanidines, built of two or more electronically coupled redox-active units, are included into the studies. The fundamental studies in TP1 are the basis for some of the work in TP2 on bond activations and catalytic applications with coordination compounds with redox-active guanidine ligands. Moreover, proton-coupled electron transfer reactions with free redox-active guanidines are studied within TP2.

具有氧化还原活性配体的配位化合物目前被深入研究，由于配体氧化还原活性产生的额外的可能性。氧化还原活性配体可以作为电子库，以提高催化应用中的底物活化。此外，氧化还原活性配体通常作为自由基配体存在，并且配体上增加的自旋密度导致特殊的配体中心反应性。最后，与氧化还原活性配体直接结合的金属的性质（例如刘易斯酸性）随着氧化还原活性配体的氧化还原状态而改变。我的研究小组研究具有氧化还原活性的胍配体的配合物。这些配体可以分为两类，胍基官能化芳族化合物（GFA），由两个或更多个胍基基团直接连接到芳族核上组成，以及脲吖嗪和相关化合物，由两个胍基基团（或相关基团）通过N-N键彼此直接连接组成。两种化合物类别均与计划的研究相关。该项目由两个分项目TP 1和TP 2组成。通过各种不同的刺激剂对分子内电子转移过程的定向刺激是TP 1的主要主题。与第一个资助期不同，第一个资助期集中在优选小的双胍和四胍配体上，由两个或更多个电子偶联的氧化还原活性单元构建的氧化还原活性寡胍被纳入研究中。TP 1中的基础研究是TP 2中关于具有氧化还原活性胍配体的配位化合物的键活化和催化应用的一些工作的基础。此外，在TP 2中研究了与自由氧化还原活性胍的质子耦合电子转移反应。