【作者】 尹帮少；

【导师】 宋礼成；

【作者基本信息】 南开大学 ， 有机化学， 2009， 博士

【摘要】 [FeFe]氢化酶是一种能高效地催化质子还原为氢气及其可逆反应的生物酶,对[FeFe]氢化酶的仿生化学研究不仅具有重要的理论意义,而且对缓解日益严重的环境污染和能源危机具有广阔的应用前景因而引起化学家们的广泛关注。为丰富和发展[FeFe]氢化酶的化学模拟工作,本文开展了新型[FeFe]氢化酶活性中心模型物的合成、结构及功能的研究,取得了如下创新性成果:1.以简单模型物[μ-SCH₂)₂NCH₂CH₂OH]Fe₂（CO）₆、[（μ-SCH₂）₂NH]Fe₂（CO）₆及[（μ-SCH₂）₂CH（OH）]Fe₂（CO）₆分别与2-C₄H₃OC（X）Cl（X=O,S）反应,合成了6个官能团化的模型物[（μ-SCH₂）₂NCH₂CH₂O₂CC₄H₃X-2]Fe₂（CO）₆（1,X=O;2,X=S）、[（μ-SCH₂）₂NC（O）CC₄H₃X-2]Fe₂（CO）₆（3,X=O;4,X=S）和[（μ-SCH₂）₂CHO₂CC₄H₃X-2]Fe₂（CO）₆（8,X=O;9,X=S）,用元素分析、IR和¹HNMR对它们进行了表征,并测定了其中5个化合物的单晶结构,用循环伏安法研究了它们的电化学性质,通过对2的电化学性质研究表明其在以弱酸醋酸作为质子源时,它能有效地电化学催化质子还原为氢气,并提出了它的催化机理。2.通过配体取代反应,合成了3个N-官能团化的氮杂卡宾取代的模型物[（μ-SCH₂）₂NCH₂CH₂O₂CCH₃]Fe₂（CO）₅L（5）、[（μ-SCH₂）₂NCH₂CH₂O₂CC₄H₃O-2]Fe₂（Co）₅L（6）和[（μ-SCH₂）₂NCH₂CH₂O₂CC₄H₃S-2]Fe₂（CO）₅L（7）（L=1-甲基-3-（2,4,6-三甲基苯基）咪唑-2-碳烯）,用元素分析、IR和¹H NMR对它们进行了表征,并测定了它们的单晶结构。红外光谱显示氮杂卡宾配体具有强的供电子能力。3.利用氮杂丙撑桥（ADT）[2Fe2S]模型物[（μ-SCH₂）₂NCH₂CH₂SC（O）CH₃]Fe₂（CO）₆分别与立方烷簇合物[PPh₄]₂[Fe₄S₄（TriS）（SEt）]及[NBu₄]₂[Fe₄S₄（TriS）（SEt）]进行酯交换及脱羰基反应,合成了两个具有[FeFe]氢化酶活性中心整体骨架结构{[2Fe2S]（μ-S）[4Fe4S]}的模型物[PPh₄]₂[Fe₄S₄（TriS）{Fe₂N（CH₂S-μ）₂（CH₂CH₂S）（CO）₅}]（17）和模型物[Bu₄N]₂[Fe₄S₄（TriS）{Fe₂N（CH₂S-μ）₂（CH₂CH₂S）（CO）₅}]（18）,通过元素分析、IR、¹H NMR和MS等手段对这两个化合物进行了表征。4.通过[（μ-SCH₂）₂NCH₂CH₂OH]Fe₂（CO）₆、[（μ-SCH₂）₂NH]Fe₂（CO）₆和[（μ-SCH₂）₂CH（OH）]Fe₂（CO）₆官能团转化反应合成了三个双蝶状的模型物C₅H₃N{[（μ-SCH₂）₂NCH₂CH₂O₂C]Fe₂（CO）₆}₂（1）、C₅H₃N{[（μ-SCH₂）₂NC（O）]Fe₂（CO）₆}₂（2）和C₅H₃N{[（μ-SCH₂）₂CHO₂C]Fe₂（CO）₆}₂（3）,用元素分析、IR和¹H NMR对它们进行了表征,并测定了模型物2的单晶结构。用循环伏安法研究了2的电化学性质,电化学研究表明以弱酸为质子源时,模型物2能催化质子电化学还原为氢气。5.通过官能团转化反应合成了四个三蝶状的模型物C₆H₃{[（μ-SCH₂）₂NCH₂CH₂O₂C]Fe₂（CO）₆}₃（4）、C₆H₃{[（μ-SCH₂）₂NCH₂CH₂O₂C]Fe₂（CO）₅PPh₃}₃（5）、C₆H₃{[（μ-SCH₂）₂CHCH₂O₂C]Fe₂（CO）₆}₃（6）和N{[（μ-SCH₂）₂NCH₂CH₂O₂CCH₂]Fe₂（CO）₆}₃（7）,用元素分析、IR、¹H NMR进行了表征,并测定了模型物4的单晶结构。6.分别利用模型物[（μ-SCH₂）₂NCH₂CH₂O₂CCH₃]Fe₂（CO）₆及[（μ-SCH₂）₂NCH₂CH₂O₂CC₄H₃O-2]Fe₂（CO）₆与双膦配体PPh₂CH₂CH₂PPh₂和trans-PPh₂CH=CHPPh₂反应,合成了四个双膦配体桥连的双簇N-官能团化的模型物{[（μ-SCH₂）₂NCH₂CH₂O₂CCH₃]Fe₂（CO）₅Ph₂PCH₂}₂（8）、{[μ-SCH₂)₂NCH₂CH₂O₂CCH₃]Fe₂（CO）₅Ph₂PCH}₂（9）、{[μ-SCH₂)₂NCH₂CH₂O₂CC₄H₃O-2]Fe₂（CO）₅Ph₂PCH₂}₂（10）和{[（μ-SCH₂）₂NCH₂CH₂O₂CC₄H₃O-2]Fe₂（CO）₅Ph₂PCH}₂（11）,用元素分析、IR、¹H NMR和³¹P NMR对它们进行了表征并测定了它们的晶体结构。更多还原

【Abstract】 The [FeFe] hydrogenases are highly efficient enzymes that catalyze the reduction of proton to hydrogen and the oxidation of hydrogen in microorganisms. In recent years, the biomimetic studies on chemistry of [FeFe] hydrogenases have received special attention. This is because such studies are not only of theoretical interest but also of practical importance for solving the problems of the increasingly environmental pollution and energy crisis. In order to develop the biomimetic chemistry of [FeFe] hydrogenases, we carried out studies on synthesis, structures, properties and functions of new models for [FeFe] hydrogenase active site. The main results in this thesis are described as follows:1. Six functionalized model compounds:[（μ-SCH₂）₂NCH₂CH₂O₂CC₄H₃X-2]Fe₂（CO）₆ （1, X = O; 2, X = S）, [（μ-SCH₂）₂NC（O）CC₄H₃X-2]Fe₂（CO）₆（3, X=O; 4, X = S） and [（μ-SCH₂）₂CHO₂CC₄H₃X-2]Fe₂（CO）₆（8, X = O; 9, X =S） were synthesized by reactions of [μ-SCH₂)₂NCH₂CH₂OH]Fe₂（CO）₆, [（μ-SCH₂）₂NH]Fe₂（CO）₆ and [（μ-SCH₂）₂CH（OH）]Fe₂（CO）₆ with 2-C₄H₃OC（X）Cl（X = O, S）, respectively. All of these compounds were fully characterized by elemental analysis, IR and ¹H NMR spectroscopies. Five molecular structures of these compounds were confirmed by X-ray diffraction techniques. Their electrochemical properties were studied by cyclic voltammetry experiments. The electrochemical properties of 2 indicated that it can electrocatalyze reduction of the acetic acid protons to H₂ under electrochemical conditions. The mechanism for this electrocatalytic process is proposed.2.Three N-heterocyclic carbene-substituted type model complexes:（6） and [（μ-SCH₂）₂NCH₂CH₂O₂CC₄H₃S-2]Fe₂（CO）₅L（7） （L = l-methyl-3-（2, 4, 6-tri methylphenyl）imidazol-2-ylidene） were prepared by CO substitution reactions with N-heterocyclic carbene ligand, respectively. All of these compounds were fully characterized by elemental analysis and IR and ¹H NMR spectroscopies and their molecular structures were confirmed by X-ray diffraction techniques. Their IR spectra indicated that the N-heterocyclic carbene ligand has strong electron-donating ability.3.Two model compounds: [Fe₄S₄（TriS）{Fe₂N（CH₂S-μ）₂（CH₂CH₂S）（CO）₅}][PPh₄]₂ （17） and [Fe₄S₄（TriS）{Fe₂N（CH₂S-μ）₂（CH₂CH₂S）（CO）₅}][Bu₄N]₂ （18）, which contain the {[2Fe2S]（μ-S）[4Fe4S]} structure like [FeFe] hydrogenases were synthesized through ester exchange and decarbonylation reactions of [（μ-SCH₂）₂NCH₂CH₂SC（O）CH₃]Fe₂（CO）₆ with cubane clusters [PPh₄]₂[Fe₄S₄（TriS）（SEt）] and [NBu₄]₂[Fe₄S₄（TriS）（SEt）], respectively. The two new compounds were characterized by elemental analysis, IR, ¹H NMR and MS.4.Three new double butterfly model complexes: C₅H₃N{[（μ-SCH₂）₂NCH₂CH₂O₂C]Fe₂（CO）₆} （1）, C₅H₃N{[（μ-SCH₂）₂NC（O）]Fe₂（CO）₆}₂ （2） and C₅H₃N{[（μ-SCH₂）₂CHO₂C]Fe₂（CO）₆}₂（3） were prepared through functional transformation of [（μ-SCH₂）₂NCH₂CH₂OH]Fe₂（CO）₆,[（μ-SCH₂）₂NH]Fe₂（CO）₆ and [（μ-SCH₂）₂CH（OH）]Fe₂（CO）₆, respectively. All of these compounds were fully characterized by elemental analysis, IR and ¹H NMR spectroscopies and the molecular structure of 2 was confirmed by X-ray diffraction techniques. The electrochemical properties of 2 was also studied by cyclic voltammetry experiments and its electrochemical properties indicated that it can electrocatalyze reduction of the acetic acid protons to H₂ under electrochemical conditions. 5.Four triple butterfly model complexes:C₆H₃{[（μ-SCH₂）₂NCH₂CH₂O₂C]Fe₂（CO）₆}₃（4）, C₆H₃{[（μ-SCH₂）₂NCH₂CH₂O₂C]Fe₂（CO）₅PPh₃}₃（5）,C₆H₃{[（μ-SCH₂）₂CHCH₂O₂C]Fe₂（CO）₆}₃（6） and NN{[（μ-SCH₂）₂NCH₂CH₂O₂CCH₂]Fe₂（CO）₆}₃（7） were prepared through functional transformation. All of these compounds were fully characterized by elemental analysis, IR and ¹H NMR spectroscopies and the molecular structure of 4 was confirmed by X-ray diffraction techniques.6.Four new double butterfly N-functionalized model complexes: {[（μ-SCH₂）₂NCH₂CH₂O₂CCH₃]Fe₂（CO）₅Ph₂PCH₂}₂（8）,{[μ-SCH₂)₂NCH₂CH₂O₂CCH₃] Fe₂（CO）₅Ph₂PCH}₂（9）,{[μ-SCH₂)₂NCH₂CH₂O₂CC₄H₃O-2]Fe₂（CO）₅Ph₂PCH₂}₂ （10） and {[（μ-SCH₂）₂NCH₂CH₂O₂CC₄H₃O-2]Fe₂（CO）₅Ph₂PCH}₂（11） were prepared by CO displacement of [（μ-SCH₂）₂NCH₂CH₂O₂CCH₃]Fe₂（CO）₆ and [（μ-SCH₂）₂NCH₂CH₂O₂CC₄H₃O-2]Fe₂（CO）₆ with PPh₂CH₂CH₂PPh₂ and trans-PPh₂CH=CHPPh₂,respectively.All of these compounds were fully characterized by elemental analysis , IR, ¹H NMR and ³¹P NMR spectroscopies and their molecular structures were confirmed by X-ray diffraction techniques.更多还原