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Indexed by:期刊论文

Date of Publication:2011-08-16

Journal:CHEMISTRY-A EUROPEAN JOURNAL

Included Journals:SCIE、EI

Volume:17

Issue:34

Page Number:9520-9528

ISSN No.:0947-6539

Key Words:homogeneous catalysis; isotopic labeling; neutral ligands; ruthenium; water oxidation

Abstract:Two dinuclear and one mononuclear ruthenium complexes containing neutral polypyridyl ligands have been synthesised as pre-water oxidation catalysts and characterised by (1)H and (13)C NMR spectroscopy and ESI-MS. Their catalytic water oxidation properties in the presence of [Ce(NH(4))(2)(NO(3))(6)] (Ce(IV)) as oxidant at pH 1.0 have been investigated. At low concentrations of Ce(IV) (5 mm), high turnover numbers of up to 4500 have been achieved. An (18)O-labelling experiment established that both O atoms in the evolved O(2) originate from water. Combined electrochemical study and electrospray ionisation mass spectrometric analysis suggest that ligand exchange between coordinated 4-picoline and free water produces Ru aquo species as the real water oxidation catalysts.