之前我們實驗室已合成出多個鐵硫錯合物如[PPh4][FeII(PS3”)(CH3CN)] (1) (PS3” = [P(C6H3-3-Me3Si-2-S)3]3-)，[PPh4][FeIII(PS3”)(OCH3)] (2)，[PPh4][FeIII(PS3”)(Cl)] (3)，[PPh4][Fe(PS3”)(NO)] (4)。他們都具有多硫配位基，與自然界固氮酵素的鉬鐵蛋白的鐵中心有相似的化學環境。在此篇研究我們加入大量還原劑與質子在氮氣下與錯合物進行反應，並觀察氨氣生成的量與文獻進行比較，嘗試找出反應的最佳條件使氨氣生成最大化。
除此之外，[PPh4][Fe(PS3”)(CH3CN)] (1)已經確認可以進行還原聯胺的催化反應，而且其中間產物之一的[NBu4][Fe(PS3”)(N2H4)]也被合成出來。聯胺(N2H4)是氮氣還原至氨氣反應中相當重要的中間產物，但是聯胺到氨氣中間的反應機制仍尚未明瞭。在這裡我們利用紫外光-可見光光譜、核磁共振光譜等光譜法研究其反應機構而更進一步獲得反應催化過程的資訊。除此之外，我們從催化反應中分離出一個鐵三價化合物[Fe(PS3”)(H2O)2] (5)。
先前我們實驗室合成了二價三價混合價數的雙鐵中心化合物 [P(Bn)Ph3][Fe2(PS3”)2] (6)。而在此研究中，我們合成並鑑定了三價三價化合物 [Fe2(PS3”)2] (7)，化合物7可由化合物6在空氣中氧化而得。其化合物在空氣中為穩定的結構，以硫元素做為橋接，並且具有[Fe2S2]的中心結構。在這邊我們利用X-ray單晶繞射、紫外光-可見光光譜、核磁共振光譜、元素分析、與電噴灑游離質譜與循環伏安法詳細研究這些化合物並描述其結構與光譜。

We have synthesized several iron thiolato complexes in our lab, such as [PPh4][FeII(PS3”)(CH3CN)] (1) (PS3” = [P(C6H3-3-Me3Si-2-S)3]3-), [PPh4][FeIII(PS3”)(OCH3)] (2), [PPh4][FeIII(PS3”)(Cl)] (3) and [PPh4][Fe(PS3”)(NO)] (4). They have nitrogenase-like structure and the potential to catalytically reduce the dinitrogen to ammonia with reducing agents and protons. In this research we test their ability in catalytic reaction and find the best condition to get optimal yield of ammonia.
[PPh4][Fe(PS3”)(CH3CN)] (1) acts as a catalyst for the reduction of hydrazine to ammonia. The substrate bound adduct, [NBu4][Fe(PS3”)(N2H4)], in the catalytic pathway was also isolated. The detail of the mechanism is still not clear. In the research, spectroscopies such as UV-vis-NIR and NMR are used to monitor the catalytic cycles. The mechanistic insights are provided. In addition, an iron(III) complex, [Fe(PS3”)(H2O)2] (5) was isolated in the catalytic reaction at low temperature.
Previously, our lab has isolated a dimeric mixed-valence FeIIFeIII complex, [P(Bn)Ph3][Fe2(PS3”)2] (6). The FeIIIFeIII form of complex [Fe2(PS3”)2] (7) is isolated and characterized at this work. Complex 7 can be obtained by complex 6 with the explosure to the air. This air-stable complex has a [Fe2S2] core with two thiolato groups bridging between two iron centers.. Several physical methods such as X-ray diffraction, electronic spectroscopy, NMR spectra, elemental analysis, ESI-MS spectra and cyclic voltammograms have been used to characterize the complex.

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