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

通过调节仿生反应中金属-氧中间体的化学性质，研究了氧化还原非活性金属离子对反应速率的扩展效应。水分子对非血红素铁(III)-过氧基络合物与氧化还原不活跃的金属离子结合的氧化还原性质的影响发表在2015年欧洲期刊《化学》上。在(TMC)FeIII-(O2)-Zn2+中，两个水分子与一个锌离子配位，降低了Zn2+离子的Lewis酸性，导致(TMC)FeIII-(O2)-Zn2+的单电子还原电位增加。另一部分是[(Bn-TPEN)MnIV(O)-(HOTf)2]2+氧原子转移过程中质子(HOTf)对PPh_3的影响。研究了膦衍生物的氧化反应，特别是质子(HOTf)的影响。它通过直接氧原子转移而不是电子转移进行，尽管电子转移与相应的氧原子向硫代苯甲醚衍生物的转移形成鲜明对比。我们首次解释了当电子转移的重组能与两电子过程竞争时，电子转移的速度可以慢于两电子过程，如直接氧原子转移。

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.