Structure and reactivity of a mononuclear non-haem iron(III)-peroxo complex.
Structure and reactivity of a mononuclear non-haem iron(III)-peroxo complex.
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DOI：
10.1038/nature10535
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发表时间：
2011-10-26
期刊：
影响因子：
64.8
通讯作者：
Nam, Wonwoo
中科院分区：
文献类型：
--
作者：
Cho, Jaeheung;Jeon, Sujin;Wilson, Samuel A.;Liu, Lei V.;Kang, Eun A.;Braymer, Joseph J.;Lim, Mi Hee;Hedman, Britt;Hodgson, Keith O.;Valentine, Joan Selverstone;Solomon, Edward I.;Nam, Wonwoo
含氧单核铁物种——铁(III)-过氧、铁(III)-氢过氧和铁(IV)-氧——是含铁金属酶催化活化双氧的关键中间体。在相同的主体复合物中生成这三种活性铁-氧物种的合成类似物是很困难的，这对于阐明催化过程中铁中心结构的变化以及控制它们与底物的化学反应性的因素是必要的。在这里，我们报告了单核非血红素侧位铁（III）-过氧配合物[Fe(III)(TMC)(OO)]+的高分辨率晶体结构。我们还报告了一系列化学反应，其中这种铁(III)-过氧络合物通过质子化的短寿命中间体干净地转化为铁(III)-氢过氧络合物，[Fe(III)(TMC)(OOH)]2+。然后，通过铁(III)-过氧化氢物质的均裂O-O键裂解，这种铁(III)-过氧化氢络合物干净地转化为ferryl络合物，[Fe(IV)(TMC)(O)]2+。所有这三种铁物质（三种生物学上最相关的铁氧中间体）均已进行了光谱表征；我们注意到它们是使用简单的大环配体获得的。我们对这三种铁物质进行了相对反应性研究，结果表明铁(III)-氢过氧络合物在醛的去甲酰化反应中是三者中最具反应性的，并且它在烷基芳族化合物的C-H键活化中与铁(IV)-氧络合物具有相似的反应性。这些反应性结果表明，铁(III)-氢过氧物种在含铁酶的亲核和亲电反应中都是可行的氧化剂。
Oxygen-containing mononuclear iron species—iron(III)–peroxo, iron(III)–hydroperoxo and iron(IV)–oxo—are key intermediates in the catalytic activation of dioxygen by iron-containing metalloenzymes. It has been difficult to generate synthetic analogues of these three active iron–oxygen species in identical host complexes, which is necessary to elucidate changes to the structure of the iron centre during catalysis and the factors that control their chemical reactivities with substrates. Here we report the high-resolution crystal structure of a mononuclear non-haem side-on iron(III)–peroxo complex, [Fe(III)(TMC)(OO)]+. We also report a series of chemical reactions in which this iron(III)–peroxo complex is cleanly converted to the iron(III)–hydroperoxo complex, [Fe(III)(TMC)(OOH)]2+, via a short-lived intermediate on protonation. This iron(III)–hydroperoxo complex then cleanly converts to the ferryl complex, [Fe(IV)(TMC)(O)]2+, via homolytic O–O bond cleavage of the iron(III)–hydroperoxo species. All three of these iron species—the three most biologically relevant iron–oxygen intermediates—have been spectroscopically characterized; we note that they have been obtained using a simple macrocyclic ligand. We have performed relative reactivity studies on these three iron species which reveal that the iron(III)–hydroperoxo complex is the most reactive of the three in the deformylation of aldehydes and that it has a similar reactivity to the iron(IV)–oxo complex in C–H bond activation of alkylaromatics. These reactivity results demonstrate that iron(III)–hydroperoxo species are viable oxidants in both nucleophilic and electrophilic reactions by iron-containing enzymes.
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DOI：
10.1073/pnas.0709471104
发表时间：
2007-12-04
影响因子：
11.1
作者：
Sastri, Chivukula V.;Lee, Jimin;Nam, Wonwoo
通讯作者：
Nam, Wonwoo
影响因子：
56.9
作者：
Rittle, Jonathan;Green, Michael T.
通讯作者：
Green, Michael T.
影响因子：
16.6
作者：
Seo, Mi Sook;Kim, Ja Young;Nam, Wonwoo
通讯作者：
Nam, Wonwoo
影响因子：
56.9
作者：
Rohde, JU;In, JH;Que, L
通讯作者：
Que, L
影响因子：
4.6
作者：
Wada, A;Ogo, S;Masuda, H
通讯作者：
Masuda, H