Redox and structural properties of mixed-valence models for the active site of the [FeFe]-hydrogenase: progress and challenges.
Redox and structural properties of mixed-valence models for the active site of the [FeFe]-hydrogenase: progress and challenges.
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[FEFE] - 氢化酶的活性位点的混合价模型的氧化还原和结构特性：进步和挑战。
DOI：
10.1021/ic8007552
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发表时间：
2008-08-18
影响因子：
4.6
通讯作者：
Zampella G
中科院分区：
文献类型：
--
作者：
Justice AK;De Gioia L;Nilges MJ;Rauchfuss TB;Wilson SR;Zampella G
研究了一系列二铁(I)二硫代羰基的单电子氧化，以评估影响[FeFe]-氢化酶Hox态的这些低分子量模型的氧化态分配、结构和反应性的因素。丙二硫酸盐Fe2(S2C3H6)(CO)3(L)(dppv) （L = CO, PMe3, Pi-Pr3）在~180 mV电位下的氧化比相关的乙二硫酸盐（Angew）更温和。化学。Int。编辑。2007,46,6152)。丙二硫酸盐的中心亚甲基和膦之间的空间冲突有利于氧化形成的旋转结构。混合价阳离子的EPR谱表明，在[Fe2(S2C3H6)(CO)4(dppv)]BF4和[Fe2(S2C3H6)(CO)3(PMe3)(dppv)]BF4中，未配对电子定位在Fe(CO)（dppv）中心，与先前的乙二硫酯[Fe2(S2C2H4)(CO)3(PMe3)(dppv)]BF4相同。然而，对于[Fe2(S2CnH2n)(CO)3(Pi-Pr3)(dppv)]BF4，自旋定位在Fe(CO)2（Pi-Pr3）中心，尽管Fe(CO)（dppv）在晶体状态下旋转。然而，IR和EPR光谱以及氧化还原电位和dft计算表明，在位阻因素的驱动下，Fe(CO)2（Pi-Pr3）位点在溶液中旋转。dft计算的混合价态的部分原子电荷分析表明，顶端配位空的Fe原子是亲电性的Fe(I)中心。对[Fe2(S2C2H4)(CN)(CO)3(dppv)]进行单电子氧化，得到μ-氰基衍生物[FeI2(S2C2H4)(CO)3(dppv)](μ-CN)[FeI2(S2C2H4)(μ-CO)(CO)2(CN)(dppv)]，并对其进行了光谱表征。
The one-electron oxidations of a series of diiron(I) dithiolato carbonyls were examined to evaluate the factors that affect the oxidation state assignments, structures, and reactivity of these low-molecular weight models for the Hox state of the [FeFe]-hydrogenases. The propanedithiolates Fe2(S2C3H6)(CO)3(L)(dppv) (L = CO, PMe3, Pi-Pr3) oxidize at potentials ~180 mV milder than the related ethanedithiolates (Angew. Chem. Int. Ed. 2007, 46, 6152). The steric clash between the central methylene of the propanedithiolate and the phosphine favors the rotated structure, which forms upon oxidation. EPR spectra for the mixed-valence cations indicate that the unpaired electron is localized on the Fe(CO)(dppv) center in both [Fe2(S2C3H6)(CO)4(dppv)]BF4 and [Fe2(S2C3H6)(CO)3(PMe3)(dppv)]BF4, as seen previously for the ethanedithiolate [Fe2(S2C2H4)(CO)3(PMe3)(dppv)]BF4. For [Fe2(S2CnH2n)(CO)3(Pi-Pr3)(dppv)]BF4, however, the spin is localized on the Fe(CO)2(Pi-Pr3) center, although the Fe(CO)(dppv) site is rotated in the crystalline state. IR and EPR spectra, as well as redox potentials and DFT-calculations, suggest, however, that the Fe(CO)2(Pi-Pr3) site is rotated in solution, driven by steric factors. Analysis of the DFT-computed partial atomic charges for the mixed-valence species shows that the Fe atom featuring a vacant apical coordination position is an electrophilic Fe(I) center. One-electron oxidation of [Fe2(S2C2H4)(CN)(CO)3(dppv)]− resulted in 2e oxidation of 0.5 equiv to give the μ-cyano derivative [FeI2(S2C2H4)(CO)3(dppv)](μ-CN)[FeII2(S2C2H4)(μ-CO)(CO)2(CN)(dppv)], which was characterized spectroscopically.
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影响因子：
4.6
作者：
Fiedler, AT;Brunold, TC
通讯作者：
Brunold, TC
影响因子：
15
作者：
Boyke, CA;Rauchfuss, TB;Bénard, M
通讯作者：
Bénard, M
影响因子：
16.6
作者：
Justice, Aaron K.;Rauchfuss, Thomas B.;Wilson, Scott R.
通讯作者：
Wilson, Scott R.
DOI：
10.1039/dt9800000579
发表时间：
1980-01-01
期刊：
JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS
影响因子：
--
作者：
BAKER, PK;CONNELLY, NG;SOMERS, KR
通讯作者：
SOMERS, KR
DOI：
10.1139/cjc-77-8-1327
发表时间：
1999-08-01
期刊：
CANADIAN JOURNAL OF CHEMISTRY-REVUE CANADIENNE DE CHIMIE
影响因子：
--
作者：
Jiang, FM;Biradha, K;Zaworotko, MJ
通讯作者：
Zaworotko, MJ