Experimental and Computational Studies on the Mechanism of Transition-Metal-Catalyzed Oxidation and Halogenation Processes

过渡金属催化氧化和卤化过程机理的实验和计算研究

• 批准号: 51114190
• 负责人: Professor Dr. Peter Comba
• 金额: --
• 依托单位: Anorganisch-Chemisches Institut
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2008
• 资助国家: 德国
• 起止时间: 2007-12-31 至 2013-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/51114190?language=en
• 关键词: Experimental; Computational; Studies; Mechanism; Transition

Bacterial catechol dioxygenases are enzymes responsible for the conversion of hydroxylated aromatic into acyclic compounds and therefore play a central role within the degradation of aromatic compounds. These nonheme iron and similar copper enzymes catalyze the oxidative cleavage of aromatic C-C bonds and, depending on the position of the reactive C-C bond with respect to the hydroxyl groups of the catechol substrate, are classified into intradiol- and extradiol-cleaving catechol dioxygenases. Based on low molecular weight model compounds with bispidine-type ligands and with humic acid derivatives, we will thoroughly analyze the reaction mechanisms and product distributions. Moreover, organic substrates are transferred by the same catalyst systems to halogenated compounds, and these reactions will also be studied in detail. These studies will involve kinetic experiments, labeling studies, the trapping of reactive intermediates and their full spectroscopic characterization at low temperature and computational work to derive the relevant potential energy surfaces of the reactions and to compute the spectroscopic properties of interesting intermediate states. The detailed mechanistic information on a molecular basis of bispidine model systems will be used to model the reactivities of iron complexes without supporting bispidine ligands, and these results will be compared with similar studies of other groups within the DFG Research Group.

细菌儿茶酚双加氧酶是负责将羟基化的芳香族化合物转化为无环化合物的酶，因此在芳香族化合物的降解中起核心作用。这些非血红素铁和类似的铜酶催化芳香族C-C键的氧化裂解，并且根据反应性C-C键相对于儿茶酚底物的羟基的位置，被分类为内二醇和外二醇裂解儿茶酚双加氧酶。基于具有双吡啶型配体和腐殖酸衍生物的低分子量模型化合物，我们将深入分析反应机理和产物分布。此外，有机底物通过相同的催化剂系统转移到卤代化合物，这些反应也将被详细研究。这些研究将涉及动力学实验，标记研究，反应中间体的捕获及其在低温下的完整光谱表征和计算工作，以推导出反应的相关势能面，并计算感兴趣的中间态的光谱性质。bispidine模型系统的分子基础上的详细机制信息将被用来模拟铁络合物的反应性，而不支持bispidine配体，这些结果将与DFG研究组内的其他组的类似研究进行比较。