我們以單鐵為金屬中心與多牙配基PS3’’反應合成出[PPh4][FeIII(PS3”)(OCH3)] (1) and [PPh4][FeIII(PS3”)(Cl)] (2)的金屬錯合物。此結構已經藉由X-ray單晶繞射解出，為扭曲的雙三角錐結構，在軸位上鍵結甲氧基和氯離子。磁性研究顯示兩種錯合物都具有S=3/2的自旋態且有著C3對稱，鍵結在錯合物(1)的甲氧基不穩定，容易被乙腈分子取代形成[FeIII(PS3”)(CH3CN)]-，接著我們加入cobaltocene還原劑我們可以發現形成穩定的[FeII(PS3”)(CH3CN)]-錯合物。利用ferrocenium 氧化錯合物(2)可以得到鐵四價的錯合物[FeIV(PS3”)(Cl)]。此外我們發現鐵三價甲氧基具有很強的親和性能夠活化二氯甲烷的C-Cl鍵，而形成錯合物(2)。將錯合物一和其他具有親電性的物質芐基溴和芐基氯反應也被偵測到，此些反應是利用如紫外光-可見光-進紅外光光譜、電噴灑游離質譜、核磁共振光譜、氣相層析儀等多種方法進行分析與鑑定，在這邊顯示鐵三價與硫配位的錯合物具有親和性的反應性，於是我們可以利用此反應性和Nitrile hydratase酵素提出一個可能性的反應路徑。[PPh4][FeIII(PS3”)(OCH3)] (1) 可以和氧雜蒽(Xanthene)、芴(Fluorene)、9,10-二氫蒽(DHA)化合物反應進行碳氫鍵斷裂的催化反應，利用紫外光-可見光-進紅外光光譜進行分析與鑑定。當[PPh4][FeIII(PS3”)(OCH3)] (1)在有水的情況下時可與水反應產生氫氣，可以利用氣相層析儀進行分析與鑑定。

Two mononuclear non-heme FeIII complexes supported by a tris(benzenethiolato)phosphine derivative, [FeIII(PS3”)(OCH3)]- (the anion of 1) and [FeIII(PS3”)(Cl)]- (the anion of 2) have been synthesized and characterized. The FeIII centers adopt trigonal-bipyramidal geometry with a methoxide or a chloride binding in the axial position. The bound methoxide in FeIII-OCH3 complex is labile and can be replaced by a CH3CN molecule. The forming FeIII-CH3CN species can be further reduced by cobaltocene quantitatively to a stable FeII-CH3CN complex, [Fe(PS3”)(CH3CN)]-, that was synthesized and characterized previously in our laboratory. The axial ligand, bound chloride, in 2 is relatively inert and stays ligated in donor solvents. One electron oxidation of [FeIII(PS3”)(Cl)]- (the anion of 2) by ferrocenium gave a FeIV analogue, [FeIV(PS3”)(Cl)]. Importantly, FeIII-OCH3 moiety in complex 1 acts as a strong nucleophile that activates the C-Cl bond in CH2Cl2, leading to the formation of FeIII-Cl complex (2) quantitatively. The nucleophilic reactions of complex 1 with other electrophiles, benzyl chloride and benzyl bromide were also evidenced. The chemistry shows that a FeIII bound base in a sulfur-rich ligation environment can have strong nucleophilicity and perform a nucleophilic reaction. While the pathway of nitrile hydratase has not been clearly determined, our example reported here provides a conjecture that the activation of nitrile could be through a nucleophilic attack of a FeIII bound hydroxide in the enzyme. In addition, complex 1 might undergo hydrogen atom abstraction in substract such as xanthene, flourene and DHA. More interestingly, the complex 1 in DMF reacts with H2O to evolve dihydrogen. Overall, the work demonstrates that a FeIII center binding with a tetradentae tris(thiolato)phosphine ligand provides a versatile reactivity in the axial site of trigonal bipyramidal geometry. The reactivity described at this work is summarized in the following scheme.

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