非ヘム高原子価マンガンオキソ錯体の反応性に及ぼす金属イオンの効果

2015 Fiscal Year Annual Research Report

• Project/Area Number: 14J00541
• Research Institution: Osaka University
• Principal Investigator: 尹 熙晶 大阪大学, 工学研究科, 特別研究員(PD)
• Project Period (FY): 2014-04-25 – 2016-03-31
• Keywords: electron transfer / oxygen atom transfer / metal-oxygen species / nonheme metal oxo / electrochemistry / redox-inactive metal ion / manganese

Outline of Annual Research Achievements

The extended effect of redox-inactive metal ions on the reaction rates has been studied by tuning the chemical properties of metal-oxygen intermediates in biomimetic reactions. The effect of water molecules on the redox properties of nonheme iron(III)-peroxo complexes binding redox-inactive metal ions has been published in Chemistry a European Journal 2015. The coordination of two water molecules to a Zn2+ ion in (TMC)FeIII-(O2)-Zn2+ decreases the Lewis acidity of Zn2+ ion, resulting in the increase in the one-electron reduction potentials of (TMC)FeIII-(O2)-Zn2+. The other part was the effect of proton (HOTf) in oxygen atom transfer from [(Bn-TPEN)MnIV(O)－(HOTf)2]2+ to PPh3 derivatives. The oxidation reaction of phosphine derivatives has been examined especially with regard to the effects of proton (HOTf). It proceeds via direct oxygen atom transfer rather than electron transfer even though the electron transfer is exergonic in sharp contrast to the corresponding oxygen atom transfer to thioanisole derivatives.
We have interpreted these results for the first time that the rate of exergonic electron transfer can be slower than that of the two-electron process such as direct oxygen atom transfer when the reorganization energy of electron transfer is to compete with that of the two-electron process.

Research Progress Status

27年度が最終年度であるため、記入しない。

Strategy for Future Research Activity

27年度が最終年度であるため、記入しない。

Research Products

• [Int'l Joint Research] 梨花女子大学(韓国)
  • Country Name: KOREA (REP. OF KOREA)
  • Counterpart Institution: 梨花女子大学
• [Journal Article] Tuning the Reactivity of Mononuclear Nonheme Manganese(IV)-Oxo Complex by Triflic Acid (2015)
  • Author(s): Chen, J., Yoon, H., Lee, Y.-M., Seo, M. S., Sarangi, R., Fukuzumi, S., Nam, W.
  • Journal Title: Chem. Sci. Volume: 6 Pages: 3624-3632
  • DOI: 10.1039/C5SC00535C
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Tuning the Redox Properties of Nonheme Iron(III)-Peroxo Complex Binding Redox-Inactive Zinc Ion by Water Molecules (2015)
  • Author(s): Lee, Y.-M., Bang, S., Yoon, H., Bae, S. H., Hong, S., Cho, K.-B., Sarangi, R., Fukuzumi, S., Nam, W.
  • Journal Title: Chem. Eur. J. Volume: 21 Pages: 10676-10680
  • DOI: 10.1002/chem.201502143
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant