似單氧化酵素之三鐵金屬簇化物之研究
Abstract
於先前實驗室研究結果，我們發展出配位基7-Dipy能與銅離子形成三核銅金屬簇離子化合物及三核錳金屬簇離子化合物，且在常溫常壓的狀態下，三核銅金屬簇離子化合物可加入雙氧水來有效催化環己烷(C6H14)的碳氫鍵(C-H鍵能99.3kcal/mol)，將環己烷氧化成環己醇(C6H13OH)與環己酮(C6H12O)。三核錳金屬簇離子化合物則可加入TBHP來有效催化環己烷(C6H14)的碳氫鍵(C-H鍵能99.3kcal/mol)，將環己烷氧化成環己醇(C6H13OH)與環己酮(C6H12O)。
在我的研究當中，嘗試使用鐵作為配位金屬，將7-Dipy加入三當量的FeIICl2，藉由ESI-MS光譜圖判斷，證實生成三核鐵金屬簇化物[FeIIFeIII(μ-O)FeIII(7-Dipy)(Cl)2]Cl2 (2) ，同時也對此三核鐵簇化物進行UV、CV和EPR的光譜分析。催化的部分，同樣是先選擇環己烷作為受質，加入TBHP或是雙氧水作為氧化劑，發現也可將環己烷氧化成環己醇與環己酮，對催化反應的時間追蹤做研究，也可發現反應直到10小時都可持續進行。接著便針對改變催化受質進行一連串的同質實驗，使用過的受質包括環戊烷、正戊烷、正己烷、正庚烷、正辛烷、甲苯。
而為了更進一步了解三核鐵簇化物在進行催化反應反應機構，因此我們利用對自由基相當靈敏的DMPO去檢測三核鐵金屬簇化物[FeIIFeIII(μ-O)FeIII(7-Dipy)(Cl)2]Cl2 (2) 在加入TBHP、受質環己烷與在甲醇溶劑底下進行催化反應後，立即偵測其EPR光譜，發現其光譜特性與HRP(horseradish peroxidase)/H2O2反應後類似。
In previous study, we have developed a ligand 7-Dipy witch can form a trinuclear copper complex and trinuclear manganese complex. This trinuclear copper complex catalyst is able to oxidize the C-H bonds of cyclohexane (C6H14)(C-H bond energy 99.3kcal/mol) by adding hydrogen peroxide. Cyclohexane is oxidized to cyclohexanol (C6H13OH) and cyclohexanone (C6H12O) under ambient temperature and pressure. In addition, trinuclear manganese complex is able to oxidize the C-H bonds of cyclohexane (C6H14)(C-H bond energy 99.3kcal/mol) by adding TBHP. Cyclohexane is oxidized into cyclohexanol (C6H13OH) and cyclohexanone (C6H12O) under ambient temperature and pressure. In my syudy, the 7-Dipy ligand was first used to coordinate the iron ions. According to the ESI-MS spectra, trinuclear iron complex [FeIIFeIII(μ-O)FeIII(7-Dipy)(Cl)2]Cl2 (2) is first synthesized. Its corresponding UV, CV, and EPR spectroscopy are discussed for the property in the text. This trinuclear iron complex is applied to the catalytic reaction, adopting cyclohexane as substrate and TBHP or hydrogen peroxide as oxidant. Based on GC-MS analysis, cyclohexanol and cyclohexanone are the oxygenated products. A series of substrates, cyclopentane, pentane, hexane, heptane, octane and toluene, are also employed for exploring the activity of trinuclear iron complex. To further understand the trinuclear iron complex [FeIIFeIII(μ-O)FeIII(7-Dipy)(Cl)2]Cl2 (2) carrying out catalytic reaction are free radical reaction mechanism or oxene insertion mechanism. Therefore, we designed a series of experiments using very sensitive to free radicals, DMPO to detect the trinuclear iron complex [FeIIFeIII(μ-O)FeIII(7-Dipy)(Cl)2]Cl2 (2) by adding H2O2 for the catalytic reaction whether involvement free radical mechanism. EPR spectra show an unique radical DMPO signal, which is similar to the reaction of HRP/H2O2-DMPO.
In previous study, we have developed a ligand 7-Dipy witch can form a trinuclear copper complex and trinuclear manganese complex. This trinuclear copper complex catalyst is able to oxidize the C-H bonds of cyclohexane (C6H14)(C-H bond energy 99.3kcal/mol) by adding hydrogen peroxide. Cyclohexane is oxidized to cyclohexanol (C6H13OH) and cyclohexanone (C6H12O) under ambient temperature and pressure. In addition, trinuclear manganese complex is able to oxidize the C-H bonds of cyclohexane (C6H14)(C-H bond energy 99.3kcal/mol) by adding TBHP. Cyclohexane is oxidized into cyclohexanol (C6H13OH) and cyclohexanone (C6H12O) under ambient temperature and pressure. In my syudy, the 7-Dipy ligand was first used to coordinate the iron ions. According to the ESI-MS spectra, trinuclear iron complex [FeIIFeIII(μ-O)FeIII(7-Dipy)(Cl)2]Cl2 (2) is first synthesized. Its corresponding UV, CV, and EPR spectroscopy are discussed for the property in the text. This trinuclear iron complex is applied to the catalytic reaction, adopting cyclohexane as substrate and TBHP or hydrogen peroxide as oxidant. Based on GC-MS analysis, cyclohexanol and cyclohexanone are the oxygenated products. A series of substrates, cyclopentane, pentane, hexane, heptane, octane and toluene, are also employed for exploring the activity of trinuclear iron complex. To further understand the trinuclear iron complex [FeIIFeIII(μ-O)FeIII(7-Dipy)(Cl)2]Cl2 (2) carrying out catalytic reaction are free radical reaction mechanism or oxene insertion mechanism. Therefore, we designed a series of experiments using very sensitive to free radicals, DMPO to detect the trinuclear iron complex [FeIIFeIII(μ-O)FeIII(7-Dipy)(Cl)2]Cl2 (2) by adding H2O2 for the catalytic reaction whether involvement free radical mechanism. EPR spectra show an unique radical DMPO signal, which is similar to the reaction of HRP/H2O2-DMPO.
Description
Keywords
微粒體甲烷單氧化酵素, 三核鐵金屬簇化物, 催化, particulate metnane monooxygenase, Trinuclear Iron complex, catalyst