Abstract
The new complex [Mn(bipyalk)(H 2 O)(µ-O)] 2 (OTf) 2 {bipyalk = 2-([2,2′-bipyridin]-6-yl)propan-2-olate} catalyzes oxygen evolution with a TOF of 0.0055 s –1 when driven by the sacrificial oxidant KHSO 5 in water. It is proposed on the basis of EPR experiments that the catalyst proceeds through a Mn V (µ-O) 2 Mn V =O intermediate supported by the highly donating tertiary alkoxide moiety of the ligand. The Mn(IV,IV) dimer can also be formed electrochemically from its precursor, Mn(bipyalkH)Cl 2 . A related series of bis-ligated monomers of the type [Mn n (bipyalkH x )(bipyalkH y )](PF 6 ) 2 is also reported, where the dication features Mn II , Mn III , and Mn IV oxidation states and corresponding protonation states. Electrochemical data on this series underscore the importance of proton loss at the alcohol/alkoxide moiety during oxidation to maintain low overpotentials required for catalysis.
Original language | English |
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Pages (from-to) | 2115-2123 |
Number of pages | 9 |
Journal | European Journal of Inorganic Chemistry |
Volume | 2019 |
Issue number | 15 |
DOIs | |
Publication status | Published - Apr 24 2019 |
Keywords
- High oxidation state
- Homogeneous catalysis
- Manganese
- Oxygen evolution
- Water splitting
ASJC Scopus subject areas
- Inorganic Chemistry