SusChEM: Electronic Structure and Reactivity of Peroxo- and Hydroxomanganese Compounds

在这个由化学部化学结构、动力学和机理B项目资助的项目中，堪萨斯大学化学系的Timothy Jackson教授正在研究具有有趣化学反应性的新型过氧和羟基锰配合物。本研究的目的是确定如何控制这些锰配合物的结构以实现所需的反应。这些知识可以用来降低化学转化的成本和环境足迹，并将促进对人类、植物和细菌中锰酶的理解。该项目处于无机化学、物理化学和生物化学的交叉点，为研究生和本科生提供了训练经验。前往国家实验室进行x射线吸收实验提供了同步辐射方面的培训，包括辐射安全方面的培训。这项研究通过在大学迎新日、大学迷你学院和Science on Tap上的演讲向公众传播。在这些论坛中，广泛的普通受众参与正在进行的化学研究。在本研究中使用的光谱和理论方法被纳入研究生和本科课程。这项研究与可持续化学有关，因为它使用了毒性更小、含量更丰富的锰配合物。在合成氧化催化剂中，锰(III)-过氧加合物经常被认为是形成高价锰-氧的中间体。已知锰(III)-羟基基序参与生物上重要的质子偶联电子转移反应。然而，几何和电子结构对这些化合物的反应性的影响还没有很好的定义。该项目的具体目标包括：1)研究氧化性强配体支持的锰(III)-过氧加合物的O-O键激活途径；2)探讨配体对锰(III)-过氧合物还原活化的影响；3)锰(III)-羟基配合物配体场的系统变化，以发展电子结构扰动与化学反应性之间的相关性。通过这项工作，通过化学和电化学途径深入了解过氧锰（III）物种对氧(O)-O键裂解的激活。此外，还探讨了中价羟基锰（III）的质子耦合电子转移反应。在本科生物无机课程中，学生将开发描述相关物理方法的视频模块。本研究中使用的方法被纳入研究生和本科课程。这项工作的成果通过大学和社区外展活动广泛传播。

In this project funded by the Chemical Structure, Dynamics & Mechanisms B Program of the Chemistry Division, Professor Timothy Jackson of the Department of Chemistry at the University of Kansas is investigating new manganese peroxo and hydroxo complexes with interesting chemical reactivity. The goal of this research is to determine how the structures of these manganese complexes can be controlled to impart a desired reaction. This knowledge could be used to reduce the cost and environmental footprint of chemical transformations and will advance understanding of manganese enzymes in humans, plants, and bacteria. The project lies at the interface of inorganic, physical and biological chemistry, and provides a training experience for graduate and undergraduate students. Trips to national laboratories to perform X-ray absorption experiments afford training in synchrotron radiation, including radiation safety training. This research is disseminated to the general public via presentations at University Orientation Days, the University Mini-College, and Science on Tap. In these forums, a broad, general audience engages with on-going chemical research. Spectroscopic and theoretical methods used in this research is incorporated into graduate and undergraduate courses. This research has relevance to sustainable chemistry because it uses less toxic and more abundant manganese complexes.Manganese(III)-peroxo adducts are frequently proposed as intermediates in the formation of high-valent manganese-oxo species in synthetic oxidation catalysts. Manganese(III)-hydroxo motifs are known to participate in biologically important proton-coupled electron-transfer reactions. However, the influence of geometric and electronic structure on the reactivity of these compounds is not well defined. Specific aims of the project include: 1) investigation of the O-O bond activation pathways of a manganese(III)-peroxo adduct support by an oxidatively robust ligand; 2) exploration of ligand effects on the reductive activation of manganese(III)-peroxo adducts; and 3) a systematic variation of the ligand field of manganese(III)-hydroxo complexes to develop correlations between electronic structure perturbations and chemical reactivity. Through this work, molecular-level insight into the activation of peroxomanganese(III) species for oxygen (O)-O bond cleavage through chemical and electrochemical pathways are developed. In addition, the proton-coupled electron transfer reactions of mid-valent hydroxomanganese(III) species are explored. In an undergraduate bioinorganic course,students will develop video modules describing relevant physical methods. The methods used in this research are incorporated into graduate and undergraduate courses. The results of this work are disseminated broadly through University and community outreach activities.