FUNCTIONAL MODELS FOR MMOH--REACTIVITY AND MECHANISM

结构特征与功能之间的相关性 甲烷单加氧酶(MMO)尚不清楚。大部分型号 MMO羟化酶(MMOH)的研究主要集中在结构上 和物理性质，不那么强调氧气的反应性， 而有关底物氧化反应的系统报道较少。这个 针对新双铁的发展提出了研究建议(二) 作为MMOH功能模型的复杂系统，基于统一的 提出了羟化反应机理。该方法从 一种新型双核配位配体体系的构建 卟啉单元不仅被认为是一个间隔物，而且 通过氧化还原特性完成所需的反应 金属卟啉。在一个分子中有两个铁(II)中心 相隔一定距离，并拥有协调地点将 用于反应性研究，包括氧气反应和 随后的底物氧化，特别是甲烷的转化。一个 硅支撑的双铁络合体系将被构建成模拟 蛋白质骨架保护反应性的生物系统 中间体在金属活性中心形成，阻止了它们的 涉及其他金属络合物的双分子途径的分解。 这项提议的长期目标是确定一种有效的、 甲烷转化为甲醇的催化体系 氧气作为氧化剂在温和的条件下通过详细的 MMO体系的热力学和动力学-力学研究。它是 希望这项研究的结果将在一个充满希望的世界 那里的环境污染是一个主要的问题。

The correlation between the structural features and the function of methane monooxygenase (MMO) remains to be elucidated. Most of model studies of MMO hydroxylase (MMOH) have focused primarily on structure and physical properties, with less emphasis on dioxygen reactivity, and few system was reported on the substrate oxidation reactions. The research proposal is directed toward the development of new diiron(II) complex system as functional models for MMOH, based on a unifying hydroxylation mechanism proposed. The approach begins with the construction of a dinuclear coordination ligand system with a porphyrin unit that is expected to serve as not only a spacer for the completion of the desired reaction by virtue of the redox properties of metalloporphyrins. The two iron(II) centers in a single molecule separated with certain distance and possessing coordination sites will be used for reactivity studies including dioxygen reaction and subsequent substrate oxidation, especially methane conversion. A Si-supported diiron complex system will be constructed to mimic the biological system in which the protein framework protects reactive intermediates formed in the metal active sites, preventing their decomposition by bimolecular pathways involving other metal complexes. The long-term objective of this proposal is to identify an efficient, catalytic system for the conversion of methane to methanol using dioxygen as an oxidant under mild conditions through detailed thermodynamic and kinetic-mechanistic studies of MMO system. It is hoped that the outcome of this study will be promising in a world where environmental pollution is a major concern.