XAS CHARACTERIZATION OF HIGH-VALENT IRON DIMERS RELEVANT TO METHANE MONOOXGENASE

与甲烷一氧化酶相关的高价铁二聚体的 XAS 表征

• 批准号: 8362238
• 负责人: SERENA D DE BEER GEORGE
• 金额: $ 0.19万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-01 至 2012-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8362238
• 关键词: Complex; Electrons; Funding; Generations; Grant; Hydrogen Bonding; Investigation; Ions; Iron; Ligands; Metals; Methane; Molecular Structure; Mononuclear; National Center for Research Resources; Parents; Principal Investigator; Radiation; Research; Research Infrastructure; Resources; Solutions; Source; Spectrum Analysis; United States National Institutes of Health; absorption; catalyst; cost; design; dimer; electron density; electronic structure; oxidation; phenolate; structural biology

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The aim of the current project is the synthesis and characterization of high-valent Fe-oxo complexes and their application as catalysts for selective C-H bond activation. Our strategy for stabilizing high-valent diiron units involves increasing the electron density at the iron ions by using strongly electron-donating ligands. For the ligands of the first generation, these involved strongly electron-donating s- and p-donors, namely phenolates. Detailed investigations of these complexes, particularly by -ray absorption spectroscopy (XAS), revealed that 1) the oxidation is ligand-centered and not metal-centered and 2) the oxidized species dissociate into mononuclear species. We used these results for the optimization of the ligand design. The new dinucleating ligands of the second generation have been synthesized and first investigations on their FeIIFeII, FeIIFeIII, and FeIIIFeIII complexes demonstrate the suitability of these complexes for generating high-valent dinuclear complexes, which should result in metal-centered oxidations and should possess higher stability as dinuclear entities. We propose the use of XAS to investigate the molecular and electronic structures of the parent complexes in solution as well as of the one- and two-electron oxidized species.

该副本是利用资源的众多研究子项目之一 由NIH/NCRR资助的中心赠款提供。对该子弹的主要支持 而且，副投影的主要研究员可能是其他来源提供的 包括其他NIH来源。 列出的总费用可能 代表subproject使用的中心基础架构的估计量， NCRR赠款不直接向子弹或副本人员提供的直接资金。 当前项目的目的是合成和表征高价值的Fe-oxo复合物及其作为选择性C-H键激活的催化剂的应用。我们稳定高价值二铁单元的策略涉及通过使用强烈的电子配体增加铁离子在铁离子处的电子密度。对于第一代的配体，这些配体涉及强烈的电子和p-donor，即酚酸盐。对这些复合物的详细研究，特别是通过射线吸收光谱（XAS）的详细研究表明，1）1）氧化是以配体为中心的，而不是以金属为中心的，2）氧化物种分离为单核物种。我们将这些结果用于优化配体设计。第二代的新核配体已经合成，并对其Feiifeii，Feiifeiii和Feiiiifeiiiii综合体进行了首次研究，这表明这些复合物对于产生高价值的二核复合物的适合性，这应该在金属中含有含量的氧化和更高的稳定性中具有更高的稳定性。我们建议使用XAS来研究溶液中父络合物的分子和电子结构，以及一单电子和两电子氧化物种。