在許多金屬蛋白的活性位置存在以硫為配位的鐵金屬中心。為了更了解鐵硫錯合物的配位化學，我們著重於鐵金屬與多芽配位基PS3”反應的研究(PS3” = [P(C6H3-3-Me3Si-2-S)3]3-)。於是我們在甲醇溶液中以鐵二價物質與氧氣反應而得到鐵三價甲氧基錯合物[FeIII(PS3”)OCH3][PPh4] (1)。此外我們還發現錯合物1和二氯甲烷反應可以得到[FeIII(PS3”)Cl][PPh4] (2)。由紫外光-可見光-進紅外光光譜、電噴灑游離質譜以及核磁共振光譜監測其反應性。錯合物2的形成證明錯合物1與二氯甲烷C-Cl鍵的活化。錯合物1和2經由X-光單晶繞射儀以及其他的物理方法，如紫外光-可見光-進紅外光光譜、電噴灑游離質譜、核磁共振光譜以及超導量子干涉震動磁量儀進行分析與鑑定。兩個錯合物的結構皆有一個四芽配位基PS3”和一個位於軸位與磷反式的輔助配位基，其幾何結構皆為雙三角錐。磁性研究顯示兩種錯合物都具有S = 3/2的自旋態，在雙三角錐幾何結構中屬於d5中間自旋態。

The iron centers ligated by S-donors are present in the actives sites of many metalloproteins. In order to understand basic coordination chemistry of iron sulfur complexes, we focus on the chemistry of iron species reacting with multidentate thiolato ligand, PS3” (PS3” = [P(C6H3-3-Me3Si-2-S)3]3-). As a result, an iron(III) methoxide complex, [FeIII(PS3”)OCH3][PPh4] (1), was obtained by the reaction of iron(II) species with dioxygen in methanol. Furthermore, complex 1 was found to react with dichloromethane, giving [FeIII(PS3”)Cl][PPh4] (2). The reactivity was monitored by UV-vis-NIR spectrum, ESI-MS spectrum and NMR spectrum. The formation of complex 2 demonstrates that C-Cl bond in dichloromethane was activated by complex 1. Complexes 1 and 2 were all well characterized by X-ray crystallography, as well as other physical methods such as UV-vis-NIR spectrum, ESI-MS spectrum, NMR spectrum and SQUID. The structures of both complexes adopt a trigonal bipyramidal geometry by binding to a tetradentate PS3” ligand and an axial co-ligand trans to the phosphine donor. The magnetic studies indicate that both complexes have S=3/2 spin states, consistent with d5 intermediate spin in trigonal bipyramidal geometry.

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