XAS STUDIES OF A METHANE HYDROXYLATING BINUCLEAR MODEL COMPLEX

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 合成并表征了一种新型双核铁模型络合物，它能高效地将甲烷转化为甲醇。由于其催化中间体的相对不稳定性和较短的寿命，迄今无法获得该中间体的结构数据。这里提出利用X射线吸收光谱(EDGE和EXAFS)来研究电子结构和几何结构。该中间体被认为含有一个混合价中心，特别被认为是由一个六配位的铁中心连接到六配位的铁氧基部分组成。如提案所述，通过谨慎使用从催化前体和衰变产物数据以及从其他特定模型络合物获得的信息，将区分这种混合物对中间体的前边缘、边缘和EXAFS数据的相对贡献。该络合物的表征具有几个重要的意义：在甲烷转化为甲醇的工业中，作为无机模型络合物，作为甲烷单加氧酶的甲醇转化活性中心的模型。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. A new binuclear iron model complex has been synthesized and characterized, which converts methane into methanol with high efficiency. The relative instability and short lifetime of its catalytic intermediate has thus far precluded obtaining structural data on this intermediate. It is proposed here to utilize x-ray absorption spectroscopy (edge and EXAFS) to address the electronic and geometric structure. The intermediate is thought to contain a mixed-valent site, specifically considered to be comprised of a six-coordinate ferrous center bridged to a six-coordinate ferryl-oxo moiety. Through prudent use of information obtained from data of the catalytic precursor and decay product, as well as from additional specific model complexes, the relative contributions of this mixture to the pre-edge, edge and EXAFS data of the intermediate will be separated, as described in the proposal. The characterization of this complex has several important implications: in the industrial conversion of methane to methanol, as an inorganic model complex, and as a model of the methanol-converting active site of methane monooxygenase.