在生物體中有許多金屬蛋白,其中有許多金屬蛋白是由鐵以及cysteine組成並且扮演著重要角色。因此，我們用PS3系列的硫來模擬cysteine上的硫並合成出一系列仿生錯合物，希望能夠更清楚瞭解鐵硫蛋白在生物體中的性質與作用。

在此論文研究中，我們合成[FeIII(PS3’’)(NH3)] (1)、 三價三價的 [FeIII2(PS3’’)2](2)-Diamond type 和二價三價混合價數的 [NEt4][Fe2II/III(PS3*)2] (3)，並使用多種儀器鑑定研究他們的性質。 利用1H-NMR光譜發現[FeIII(PS3’’)(NH3)] (1) 溶在THF中另外加入氨氣可以在低溫產生接上2個氨氣的六配位錯合物 [FeIII(PS3’’)(NH3)2]。我們也發現錯合物1的氨配位基在除了THF之外的有機溶劑中是不穩定的，像是在CH3CN中氨配位基容易被取代形成[PPh4][FeIII(PS3’’)(CH3CN)]。

先前我們實驗室合成並鑑定了三價三價和二價三價混合價數的雙鐵中心錯合物[Fe2III(PS3’’)2](4)-Butterfly type和[P(Bn)Ph3][Fe2II/III(PS3”)2] (5)。而在此研究中，我們合成了另一種構型的三價三價雙鐵化合物[Fe2III(PS3’’)2](2)-Diamond type和使用PS3*為配位基的二價三價混價數化合物 [NEt4][Fe2II/III(PS3*)2] (3)。 這四種雙鐵中心錯合物和Rieske proteins的模板錯合物相似。 在此論文我們利用許多儀器鑑定化合物2和3並描述其結構與光譜。

The interaction of transition metal ions with sulfur containing bioligands such as cysteine is an essential subject in various biological and medical aspects. Thus, efforts have been made on understanding fundamental chemistry of iron complexes with thiolato ligands that mimic S-donors in cysteine. Against this motivation, we focus on iron thiolate chemistry at this work.

At this work, We have synthesized [FeIII(PS3’’)(NH3)] (1), all-ferric [FeIII2(PS3’’)2](2)-Diamond type and mixed valence [NEt4][Fe2II/III(PS3*)2] (3). We used several physical methods to characterize complexes 1, 2 , 3 and study their chemistry at this work. With the evidence of 1H-NMR spectra, we found complex 1 can form [FeIII(PS3’’)(NH3)2] with excess ammonia gas at low temperature. In addition, NH3 ligand of complex 1 is labile in the most organic solvents except THF. In CH3CN solution, CH3CN molecule replaces bound NH3 molecule in 1 to form [PPh4][FeIII(PS3’’)(CH3CN)]. Previously in our laboratory, other diiron complexes with PS3” ligand were isolated and characterized. They are [Fe2III(PS3’’)2](4)-Butterfly type and [P(Bn)Ph3][Fe2II/III(PS3”)2] (5). Together with complexes 2 and 3, they represent model complexes for Rieske proteins. All complexes presented here were well characterized by X-ray diffraction, electronic spectroscopy, NMR spectroscopy, elemental analysis, ESI-MS spectrometry, cyclic voltammograms, EPR and SQUID.

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