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Amphiphilic Oxo-Bridged Ruthenium "Green Dimer" for Water Oxidation.

ABSTRACT: In 1982, an oxo-bridged dinuclear ruthenium(III) complex, known as "blue dimer," was discovered to be active for water oxidation. In this work, a new amphiphilic ruthenium "green dimer" 2, obtained from an amphiphilic mononuclear Ru(bda) (N-OTEG) (L1) (1; N-OTEG = 4-(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)-pyridine; L1 = vinylpyridine) is reported. An array of mechanistic studies identifies "green dimer" 2 as a mixed valence of Ru^II-O-Ru^III oxo-bridged structure. Bearing the same bda^2- and amphiphilic axial ligands, monomer 1 and green dimer 2 can be reversibly converted by ascorbic acid and oxygen, respectively, in aqueous solution. More importantly, the oxo-bridged "green dimer" 2 was found to take water nucleophilic attack for oxygen evolution, in contrast to monomer 1 via radical coupling pathway for O-O bond formation. This is the first report of an amphiphilic oxo-bridged catalyst, which possesses a new oxygen evolution pathway of Ru-bda catalysts.

SUBMITTER: Yang QQ

PROVIDER: S-EPMC7090326 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Amphiphilic Oxo-Bridged Ruthenium "Green Dimer" for Water Oxidation.

Yang Qing-Qing QQ Jiang Xin X Yang Bing B Wang Yang Y Tung Chen-Ho CH Wu Li-Zhu LZ

iScience 20200308 3

In 1982, an oxo-bridged dinuclear ruthenium(III) complex, known as "blue dimer," was discovered to be active for water oxidation. In this work, a new amphiphilic ruthenium "green dimer" 2, obtained from an amphiphilic mononuclear Ru(bda) (N-OTEG) (L1) (1; N-OTEG = 4-(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)-pyridine; L1 = vinylpyridine) is reported. An array of mechanistic studies identifies "green dimer" 2 as a mixed valence of Ru<sup>II</sup>-O-Ru<sup>III</sup> oxo-bridged structure. Bearing the s ...[more]

PMID: 32200095

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