Metal-Oxo and Metal-Peroxo Intermediates in Oxidative Catalysis

无机化学、生物无机化学和金属有机化学项目的这一奖项支持普林斯顿大学约翰·T·格罗夫斯教授的研究，涉及三个相互关联的领域：(1)金属卟啉介导的氧活化和转移，(2)水溶液中高价铁的化学和氧化催化，(3)铑和钴卟啉对烯烃和烷烃的官能化。氧-锰(V)卟啉络合物具有不寻常的反应活性，与更多的缺电子卟啉导致更稳定的氧化剂。这种意想不到的行为的假设是，自旋态交叉和金属配位水的酸度变化导致催化剂活性的变化。快速动力学技术将使用一系列相关的铬、锰和铁催化剂来验证这一假说。氧金属卟啉可以快速、可逆地将其氧合配体转移到溴离子上。正向反应模拟卤代过氧化物酶催化的卤化物氧化反应，反向反应是金属卟啉催化底物氧化的催化剂活化步骤。描述了这些活性中间体的完整的能量图谱的实验。这些信息将被用来实现次氯酸盐的催化形成和水的氧化。通过对实现催化所需的几个反应步骤的分析，以及开发使这些反应实用的方法，也正在对烯烃的催化反Markovnikov氢官能化进行研究。这项研究旨在发现化学催化的基本原理，并利用这些洞察力来推动下一代催化剂的发明。这项努力还旨在培训国家实现这些发现所提供的技术进步所需的人员，并为未来培训科学教师。氧化催化方面的新发现和新发明对于解决当前使用的技术引起的制造和环境问题是必要的。

This award in the Inorganic, Bioinorganic and Organometallic Chemistry program supports research by Professor John T. Groves at Princeton University involving research in three inter-related areas: (1) Oxygen activation and transfer mediated by metalloporphyins, (2) Chemistry and oxidative catalysis by high-valent iron in aqueous solution, (3) Alkene and Alkane functionalization by rhodium and cobalt porphyrins. Oxo-manganese(V) porphyrin complexes have an unusual reactivity profile with more electron deficient porphyrins leading to more stable oxidants. The hypothesis for this unexpected behavior is that spin state crossings and variations in the acidty of metal-coordinated water lead to variations in catalyst activity. Rapid kinetic techniques will be used to test this hypothesis using a related family of Cr, Mn, and Fe catalysts. Oxometalloporphyrins can efficiently transfer their oxo ligand to bromide ion in a rapid and reversible manner. The forward reaction mimics the halide oxidation reaction catalyzed by haloperoxidases, while the reverse reaction is the catalyst activation step in substrate oxygenation by metalloporphyrins. Experiments are described for the complete mapping of the energetics of these reactive intermediates. This information will be used to achieve the catalytic formation of hypochlorite and the oxidation of water. An approach is also being taken to the catalytic anti-Markovnikov hydrofunctionalization of olefins through the analysis of the several reaction steps required to achieve catalysis and developing methods to make these reactions practical. The research aims to discover the basic principles by which chemical catalysis operates and to use those insights to drive the invention of the next generation of catalysts. The effort also aims to train the personnel that are necessary for the nation to achieve the technological advances offered by these discoveries and to train the teachers of science for the future. New discoveries and invention in oxidative catalysis are necessary to address both manufacturing and environmental concerns arising from presently used technologies.