Mechanism of H <sup>+</sup> dissociation?induced O?O bond formation via intramolecular coupling of vicinal hydroxo ligands on low-valent Ru(III) centers
Mechanism of H <sup>+</sup> dissociation?induced O?O bond formation via intramolecular coupling of vicinal hydroxo ligands on low-valent Ru(III) centers
复制标题
H <sup> </sup> 解离机制？通过低价 Ru(III) 中心上邻位羟基配体的分子内偶联诱导 O?O 键形成
DOI：
10.1073/pnas.2113910118
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Yagi Masayuki
中科院分区：
文献类型：
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作者：
Tanahashi Yuki;Takahashi Kosuke;Tsubonouchi Yuta;Nozawa Shunsuke;Adachi Shin-ichi;Hirahara Masanari;Mohamed Eman A.;Zahran Zaki N.;Saito Kenji;Yui Tatsuto;Yagi Masayuki
了解O-O键的形成对于揭示光合作用中水分氧化的机理和开发人工光合作用中高效的水分氧化催化剂具有重要意义。从光谱和理论上研究了RuII 2（OH）（OH2）核与邻位OH和OH2配体的化学氧化反应，为核中O-O键的形成提供了一种机理性的见解.我们证明了低价RuIII2（OH）核与邻位OH配体形成O-O键，形成具有μ-OOH桥的RuII2（μ-OOH）核。O-O键的形成是由RuIII2（OH）2的一个OH配体通过OH和去质子化的O −配体的分子内偶联而去质子化诱导的，共轭的是从两个RuIII中心到它们的配体的双电子转移。RuII 2（μ-OOH）的单重态和三重态之间的系统间交叉很容易通过μ-OOH桥和辅助骨架配体之间的H+交换来切换。
The understanding of O–O bond formation is of great importance for revealing the mechanism of water oxidation in photosynthesis and for developing efficient catalysts for water oxidation in artificial photosynthesis. The chemical oxidation of the RuII2(OH)(OH2) core with the vicinal OH and OH2ligands was spectroscopically and theoretically investigated to provide a mechanistic insight into the O–O bond formation in the core. We demonstrate O–O bond formation at the low-valent RuIII2(OH) core with the vicinal OH ligands to form the RuII2(μ-OOH) core with a μ-OOH bridge. The O–O bond formation is induced by deprotonation of one of the OH ligands of RuIII2(OH)2via intramolecular coupling of the OH and deprotonated O−ligands, conjugated with two-electron transfer from two RuIIIcenters to their ligands. The intersystem crossing between singlet and triple states of RuII2(μ-OOH) is easily switched by exchange of H+between the μ-OOH bridge and the auxiliary backbone ligand.