High-Valent Metal Oxos to Model OEC in Photosystem II

高价金属 Oxos 在 Photosystem II 中模拟 OEC

• 批准号: 7054996
• 负责人: Theodore A Betley
• 金额: $ 4.4万
• 依托单位: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-12-01 至 2007-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7054996
• 关键词: biomimetics; catalyst; chemical association; chemical binding; chemical bond; chemical kinetics; chemical models; electron transport; ligands; manganese; model design /development; oxidation reduction reaction; oxygen; oxygen compounds; photolysis; photosynthetic reaction centers; photosystem; postdoctoral investigator; protein structure function; water

DESCRIPTION (provided by applicant): The proposed research is designed to provide mechanistic insight into the water-splitting reaction that occurs at the oxygen-evolving complex (OEC) in photosystem II. Specifically, a research plan is presented that describes the preparation of novel trianionic, tris(arylphenoxide) ligands to accomplish the following: (1) the generation of high-valent metal oxo complexes to serve as OEC mimics, (2) investigate the metal oxo generation and stability as a function of secondary bonding environments; (3) probe the mechanism of O-O bond forming reactions relevant to the OEC and other functional models; and (4) make progress towards the ultimate goal of realizing a sustainable water-splitting catalyst. Controlling the secondary bonding environments will be critical for stabilizing high-valent metal oxo species, bringing two water molecules into a close proximity for coupling, and tuning the redox potential of the oxo and the pKa of incoming oxygen nucleophiles.The models described herein are unique in that they will facilitate both acid-base and radical- coupling O-O bond forming reaction mechanisms to be investigated.

描述（由申请人提供）：拟议的研究旨在提供对光系统 II 中的析氧复合物 (OEC) 发生的水分解反应的机制见解。具体来说，提出了一项研究计划，描述了新型三阴离子三（芳基苯氧基）配体的制备，以实现以下目标：（1）生成高价金属氧配合物以用作OEC模拟物，（2）研究金属氧的生成和稳定性作为二次键合环境的函数； (3) 探讨与OEC及其他功能模型相关的O-O键形成反应机制； (4)朝着实现可持续水分解催化剂的最终目标取得进展。控制二次键合环境对于稳定高价金属氧物种、使两个水分子紧密接近以进行偶联以及调节氧的氧化还原电位和引入的氧亲核试剂的 pKa 至关重要。本文描述的模型的独特之处在于它们将促进酸碱和自由基偶联 O-O 键形成反应机制的研究。