Evaluating the identity and diiron core transformations of a (μ-oxo)diiron(III) complex supported by electron-rich tris(pyridyl-2-methyl)amine ligands.
Evaluating the identity and diiron core transformations of a (μ-oxo)diiron(III) complex supported by electron-rich tris(pyridyl-2-methyl)amine ligands.
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评估由富含电子的Tris（吡啶基-2-甲基）胺配体支持的（μ-oxo）二氮（III）复合物的身份和二铁核转化。
DOI：
10.1021/ic202379b
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发表时间：
2012-02-20
影响因子：
4.6
通讯作者：
Lippard SJ
中科院分区：
文献类型：
--
作者：
Do LH;Xue G;Que L Jr;Lippard SJ
研究了由三((3,5-二甲基-4-甲氧基)吡啶基-2-甲基)胺(R3TPA)配体配位的(μ-氧代)二铁(III)络合物的组成。使用各种光谱方法和 X 射线晶体学进行表征表明，高氯酸铁 (III)、氢氧化钠和 R3TPA 反应生成 [Fe2(μ-O)(μ-OH)(R3TPA)2](ClO4)3 (2)，而不是之前报道的物质 [Fe2(μ-O)(OH)(H2O)(R3TPA)2](ClO4)3 (1)。在水存在和低温下，2 的 (μ-氧代)(μ-羟基)二铁(III) 核容易转化为 1 的(μ-氧代)(羟基)(水)二铁(III) 核。当 2 在室温下暴露于湿乙腈时，CH3CN 加合物水解为 CH3COO−，形成化合物 [Fe2(μ-O)(μ-CH3COO)(R3TPA)2](ClO4)3 (10)。通过将 10 的光谱特性与独立制备的样品的光谱特性进行比较，确认了 10 的身份。为了评估 1 和 2 是否能够生成二铁 (IV) 物质 [Fe2(μ-O)(OH)(O)(R3TPA)2]3+ (4)（之前已作为高价二铁蛋白含氧中间体的合成模型生成），进行了研究以调查其与过氧化氢的反应性。由于 2 在 CH3CN 中与过氧化氢反应迅速，但在 CH3CN/H2O 中则不然，因此有利于转化为 1 的条件，因此配合物 1 不太可能是 4 的前体。在缺乏腈的溶剂中，2 与 H2O2 反应时也会形成化合物 4，这表明 CH3CN 的水解不参与 H2O2 活化反应。这些发现揭示了富电子 R3TPA 配体的几种二铁配合物的形成，并详细阐述了使用该配体框架生成二铁 (IV) 蛋白中间体合成模型所需的条件。
The composition of a (μ-oxo)diiron(III) complex coordinated by tris((3,5-dimethy-4-methoxy)pyridyl-2-methyl)amine (R3TPA) ligands was investigated. Characterization using a variety of spectroscopic methods and X-ray crystallography indicated that the reaction of iron(III) perchlorate, sodium hydroxide, and R3TPA affords [Fe2(μ-O)(μ-OH)(R3TPA)2](ClO4)3 (2), rather than the previously reported species, [Fe2(μ-O)(OH)(H2O)(R3TPA)2](ClO4)3 (1). Facile conversion of the (μ-oxo)(μ-hydroxo)diiron(III) core of 2 to the (μ-oxo)(hydroxo)(aqua)diiron(III) core of 1 occurs in the presence of water and at low temperature. When 2 is exposed to wet acetonitrile at room temperature, the CH3CN adduct is hydrolyzed to CH3COO−, which forms the compound [Fe2(μ-O)(μ-CH3COO)(R3TPA)2](ClO4)3 (10). The identity of 10 was confirmed by comparison of its spectroscopic properties with those of an independently prepared sample. To evaluate whether or not 1 and 2 are capable of generating the diiron(IV) species [Fe2(μ-O)(OH)(O)(R3TPA)2]3+ (4), which has previously been generated as a synthetic model for high-valent diiron protein oxygenated intermediates, studies were performed to investigate their reactivity with hydrogen peroxide. Because 2 reacts rapidly with hydrogen peroxide in CH3CN but not in CH3CN/H2O, conditions that favor conversion to 1, complex 1 is not a likely precursor to 4. Compound 4 also forms in the reaction of 2 with H2O2 in solvents lacking a nitrile, suggesting that hydrolysis of CH3CN is not involved in the H2O2 activation reaction. These findings shed light on the formation of several diiron complexes of electron-rich R3TPA ligands and elaborate on conditions required to generate synthetic models of diiron(IV) protein intermediates with this ligand framework.
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影响因子：
4.6
作者：
Praneeth, VKK;Näther, C;Lehnert, N
通讯作者：
Lehnert, N
影响因子：
15
作者：
Zheng, H;Zang, Y;Que, L
通讯作者：
Que, L
影响因子：
15
作者：
DONG, YH;FUJII, H;MUNCK, E
通讯作者：
MUNCK, E
影响因子：
15
作者：
SANDERSLOEHR, J;WHEELER, WD;LOEHR, TM
通讯作者：
LOEHR, TM
C-H键裂解的合成[Fe2（μ-O）2]钻石核的底物触发的激活。
影响因子：
15
作者：
Xue, Genqiang;Pokutsa, Alexander;Que, Lawrence, Jr.
通讯作者：
Que, Lawrence, Jr.