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研究生: 黃柏華
Huang, Bo-Hua
論文名稱: 鈷與鎳磷硫配位化合物產生氫氣的探討及其合成與鑑定
Synthesis and Characterization of Cobalt and Nickel Thiolate Complexes for Hydrogen evolution
指導教授: 許鏵芬
Hsu, Hua-Fen
學位類別: 碩士
Master
系所名稱: 理學院 - 化學系
Department of Chemistry
論文出版年: 2015
畢業學年度: 103
語文別: 英文
論文頁數: 70
中文關鍵詞: 磷硫配位基鈷硫錯合物鎳硫錯合物雙核鎳硫錯合物釋放氫氣
外文關鍵詞: thiolatophosphine ligands, cobalt thiolate complex, nickel thiolate complex, hydrogen evolution
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  • 在再生能源中,使用第一列過度金屬為高效率催化劑將質子還原成氫氣的研究是很大的挑戰。第一列過度金屬為理想的催化劑由於在地球上是高含量且低成本的金屬。基於此動機,我們的目標是發展鈷與鎳金屬催化劑來催化質子形成氫氣。在此研究中,我們使用三芽磷硫配位基[PS2”]H2來探討鈷與鎳金屬的化學(PS2”H2 = [P(C6H5)(C6H3-3-Me3Si-2-SH)2])。鎳二價物質與[PS2"]H2反應得到鎳二價錯合物[NiII(PSSH”)2] (1),錯合物1經由X-光單晶繞射儀、紫外-可見光-進紅外光光譜、電噴灑游離質譜以及核磁共振光譜進行分析與鑑定。此外我們還發現錯合物1與氧氣反應後可以得到[NiIV(PS2”)2] (2)。錯合物2經由X-光單晶繞射儀、紫外-可見光-進紅外光光譜、核磁共振光譜以及循環伏安法進行分析與鑑定。將錯合物1照光後可以得到錯合物2而且釋放出氫氣,此部分使用氣相層析儀與電噴灑質譜證明。鎳二價物質與[PS2"]H2反應得到雙核鎳二價錯合物[NiII(PS2”)2]2 (3),錯合物3經由X-光單晶繞射儀、紫外-可見光-進紅外光光譜以及核磁共振光譜進行分析與鑑定。鈷二價物質與[PS2”]H2反應得到鈷三價錯合物[PPh4][Co(PS2”)2] (4)。錯合物4經由X-光單晶繞射儀、元素分析儀、紫外-可見光-進紅外光光譜、電噴灑游離質譜、核磁共振光譜以及循環伏安法進行分析與鑑定。

    A challenge to produce dihydrogen for renewable energy is to develop high efficient catalysts for proton reduction. The first-row transition metal complexes are ideal catalysts due to their low cost and high abundance in the earth. Based on this motivation, we have been aiming on develop nickel and cobalt catalysts that carry the reduction of proton to dihydrogen. In this study, bis(benzenethiolato)phosphine ligand derivative, [PS2”]H2 (PS2”H2 = [P(C6H5)(C6H3-3-Me3Si-2-SH)2]) was used to explore nickel and cobalt chemistry. A nickel(II) thiolate complex, [NiII(PSSH”)2] (1), was obtained by the reaction of nickel(II) species with [PS2”]H2. Complex 1 was characterized by X-ray crystallography, UV-vis-NIR spectrum, ESI-MS spectrum and NMR spectrum. Furthermore, complex 1 was found to react with oxygen and produce a nickel(IV) species, [NiIV(PS2”)2] (2). Complex 2 was characterized by X-ray crystallography, UV-vis-NIR spectrum, NMR spectrum and cyclic voltammetry. Importantly, the irradiation of complex 1 produced dihydrogen that was identified by gas chromatography. On the same time, complex 1 was changed to complex 2 that was characterized by ESI-MS spectrum. A dinickel(II) thiolate complex, [NiII(PS2”)2]2 (3), was obtained by the reaction of nickel(II) species with [PS2”]H2. The complex 3 was characterized by X-ray crystallography, UV-vis-NIR spectrum and NMR spectrum. A cobalt(III) thiolate complex, [PPh4][Co(PS2”)2] (4), was obtained by the reaction of cobalt(II) species with [PS2”]H2. The complex 4 was characterized by X-ray crystallography, element analysis, UV-vis-NIR spectrum, ESI-MS spectrum, NMR spectrum and cyclic voltammetry.

    List of Contents Abstract I 中文摘要 II 誌謝 III List of Contents IV List of Schemes VII List of Tables VIII List of Figures IX Abbreviations XII Chapter 1. Introduction 1 1-1 Hydrogen sustainable energy. 1 1-2 Hydrogenase. 1 Hydrogenases 1 [FeFe]-hydrogenase. 2 [NiFe]-hydrogenase. 3 [Fe]-hydrogenase. 4 1-3 Biomimetic complexes. 4 Biomimetic complexes for [FeFe]-H2ases. 5 Biomimetic complexes for [NiFe]-H2ases. 6 Biomimetic complexes for [Fe]-H2ases. 7 1-4 Photocatalytic and electrocatalytic production of hydrogen systems. 7 Complexes of photocatalytic and electrocatalytic for hydrogen evolution. 8 1-5 Motivation of this work. 9 Chapter 2. Results and Discussion 10 2-1 Synthesis and characterization of [NiII(PSSH”)2] (1). 10 Synthesis. 10 The X-ray structure. 10 The IR spectrum. 13 Elemental analysis. 15 The UV-vis-NIR spectrum. 15 The ESI-MS spectrum. 16 The 1H NMR spectrum. 17 The 31P NMR spectrum. 18 2-2 Synthesis and characterization of [NiIV(PS2”)2] (2). 19 Synthesis. 19 The X-ray structure. 19 The UV-vis-NIR spectrum. 22 The 1H NMR spectrum. 23 The 31P NMR spectrum. 24 The electrochemical study. 24 2-3 Synthesis and characterization of [NiII(PS2”)2]2 (3). 27 Synthesis. 27 The X-ray structure. 27 The UV-vis-NIR spectrum. 30 The 1H NMR spectrum. 31 The 31P NMR spectrum. 32 2-4 Synthesis and characterization of [PPh4][Co(PS2”)2] (4). 33 Synthesis. 33 The X-ray structure. 33 Elemental analysis. 36 The UV-vis-NIR spectrum. 37 The ESI-MS spectrum. 37 The 1H NMR spectrum. 39 The 31P NMR spectrum. 39 The electrochemical study. 40 2-5 The studies for hydrogen evolution of [NiII(PSSH”)2] (1). 43 Hydrogen peak in Gas Chromatograph. 43 Hydrogen evolution of [NiII(PSSH”)2] (1) with irradiation. 43 ESI-MS studies. 45 Proposed mechanisms. 46 Chapter 3. Conclusions 47 Chapter 4. Experiment and Instruments 48 4-1 General procedures materials. 48 4-2 Synthesis. 49 Orthotrimethylsilylthiophenol 49 [PS2”]H2, ([P(C6H5)(C6H3-3-Me3Si-2-SH)2]) 49 [NiII(PSSH”)2] (1) 50 [NiIV(PS2”)2] (2) 51 [NiII(PS2”)2]2 (3) 51 [PPh4][Co(PS2”)2] (4) 52 4-3 Instruments. 53 Elemental analysis. 53 X-ray crystallographic data collection of the structures. 53 Ultraviolet-visible spectroscopy. 53 Electrospray ionization mass spectrometry. 53 Infrared Spectroscopy. 54 Nucleic Magnetic Resonance Spectroscopy. 54 Cyclic Voltammetry. 54 Gas Chromatograph. 54 Reference 55 Appendix A 58 Appendix B 59 CIF check of [NiII(PSSH”)2] (1) 59 Appendix C 62 CIF check of [NiIV(PS2”)2] (2) 62 Appendix D 65 CIF check of [NiII(PS2”)2]2 (3) 65 Appendix E 68 CIF check of [PPh4][Co(PS2”)2] (4) 68 List of Schemes Scheme 2-1. Synthesis of [NiII(PSSH”)2] (1). 10 Scheme 2-2. Synthesis of [NiIV(PS2”)2] (2). 19 Scheme 2-3. Synthesis of [NiII(PS2”)2]2 (3). 27 Scheme 2-4. Synthesis of [PPh4][Co(PS2”)2] (4). 33 List of Tables Table 2-1-1. Crystal data and refinement parameters for complex 1. 11 Table 2-1-2. Selected bond distances (Å) of [NiII(PSSH”)2] (1) 12 Table 2-1-3. Selected angles (deg) of [NiII(PSSH”)2] (1) 12 Table 2-1-4. Element Analysis of [NiII(PSSH”)2](1) 15 Table 2-2-1. Crystal data and refinement parameters for complex 2. 20 Table 2-2-2. Selected bond distances (Å) of [NiIV(PS2”)2]•CH2Cl2 ( 2•CH2Cl2) 21 Table 2-2-3. Selected angles (deg) of [NiIV(PS2”)2]•CH2Cl2 ( 2•CH2Cl2) 21 Table 2-3-1. Crystal data and refinement parameters for complex 3. 28 Table 2-3-2. Selected bond distances (Å) of [NiII(PS2”)2]2 (3) 29 Table 2-3-3. Selected angles (deg) of [NiII(PS2”)2]2 (3) 29 Table 2-4-1. Crystal data and refinement parameters for complex 4. 34 Table 2-4-2. Selected bond distances (Å) of [PPh4][Co(PS2”)2]•CH3OH (4 •CH3OH) 35 Table 2-4-3. Selected angles (deg) of [PPh4][Co(PS2”)2]•CH3OH (4 •CH3OH) 35 Table 2-4-4. Element Analysis of [PPh4][Co(PS2”)2]•CH3OH (4 •CH3OH) 36 List of Figures Figure 1-2-1. Active sites of the [NiFe]-, [FeFe]- and [Fe]-hydrogenases (Fe-GP cofactor). 1 Figure 1-2-2. Proposed catalytic cycle for H2 generation and uptake at the [FeFe]-hydrogenase active site with possible oxidation states for the intermediates.6 2 Figure 1-2-3. Suggested catalytic cycle for [Ni-Fe]-hydrogenase.7 3 Figure 1-2-4. Reaction of methenyl-H4MPT+ with H2.5 4 Figure 1-3-1. The model complexes of [FeFe]-hydrogenase. 5 Figure 1-3-2. The model complexes of [NiFe]-hydrogenase. 6 Figure 1-3-3. The model complexes of [Fe]-hydrogenase. 7 Figure 1-4-1. The cobalt and nickel complexes of photocatalytic and electrocatalytic systems. 8 Figure 1-5-1. The structure of ligand, [PS2”]H2 9 Figure 2-1-1. ORTEP diagram of [NiII(PSSH”)2] (1) which has the agnostic interaction, M…H-S shown with 35% thermal ellipsoids. H atoms (except H1) are omitted for clarity. 12 Figure 2-1-2. Solid state of [NiII(PSSH”)2] (1) has intramolecular pi-pi stacking from the phenyl group of different ligands. H atoms (except H1) are omitted for clarity. 13 Figure 2-1-3. The IR spectrum of [NiII(PSSH”)2] (1). 14 Figure 2-1-4. The conjecture of structure isomerisms of [NiII(PSSH”)2].(The crystallographic data gives trans-[NiII(PSSH”)2] (1).) 14 Figure 2-1-5. UV-vis-NIR spectrum of [NiII(PSSH”)2](1) in 0.2 mM CH2Cl2. 15 Figure 2-1-6. The ESI-MS spectrum of [NiII(PSSH”)2] - in negative mode. 16 Figure 2-1-7. The isotope spectrum of [NiII(PSSH”)2] - in negative mode. (A is experiment value and B is calculated value ). 16 Figure 2-1-8. The 1H NMR spectrum of [NiII(PSSH”)2] (1) in d8-THF. Inset (top): The 1H NMR spectrum range at 6.7-8.3 ppm.. Inset (bottom): The 1H NMR spectrum range at 5.5-5.8 ppm.. 17 Figure 2-1-9. The 31P NMR spectrum of [NiII(PSSH”)2] (1) in d8-THF. 18 Figure 2-2-1. ORTEP diagram of [NiIV(PS2”)2]•CH2Cl2 (2•CH2Cl2) which has intramolecular pi-pi stacking from the phenyl group of different ligands shown with 35% thermal ellipsoids. H atoms, and solvated CH2Cl2 are omitted for clarity. 21 Figure 2-2-2. ORTEP diagram of the metal center of [NiIV(PS2”)2]•CH2Cl2 ( 2•CH2Cl2), showing a distorted octahedral geometry. 22 Figure 2-2-3. UV-vis-NIR spectrum of [NiIV(PS2”)2] (2) in 0.2 mM CH2Cl2 . 22 Figure 2-2-4. The 1H NMR spectrum of [NiIV(PS2”)2] (2) in CD2Cl2. Inset: The 1H NMR spectrum range at 6.5-7.6 ppm.. 23 Figure 2-2-5. The 31P NMR spectrum of [NiIV(PS2”)2] (2) in CD2Cl2. 24 Figure 2-2-6. The cyclic voltammogram of [NiIV(PS2”)2] (2) in CH2Cl2 solution (scan rate :0.1Vs-1) 25 Figure 2-2-7. The cyclic voltammogram of [NiIV(PS2”)2] (2) at range -0.4V to 1.1V in CH2Cl2 solution (scan rate :0.1Vs-1) 26 Figure 2-2-8. The cyclic voltammogram of [NiIV(PS2”)2] (2) at range -0.3V to -1.6V in CH2Cl2 solution (scan rate :0.1Vs-1) 26 Figure 2-3-1. ORTEP diagram of [NiII(PS2”)2]2 (3) shown with 35% thermal ellipsoids. H atoms are omitted for clarity. 29 Figure 2-3-2. ORTEP diagram of metal center of [NiII(PS2”)2]2 (3) and dihedral angel between the S2-Ni1-S3/S2-Ni2-S3 planes. 30 Figure 2-3-3. Solid state of [NiII(PS2”)2]2 (3) has weak intramolecular pi-pi stacking from the phenyl group of different ligands. 30 Figure 2-3-4. UV-vis-NIR spectrum of [NiII(PS2”)2]2 (3) in 0.17 mM CH2Cl2. 31 Figure 2-3-5. The 1H NMR spectrum of [NiII(PS2”)2]2 (3) in CD2Cl2. 31 Figure 2-3-6. The 31P NMR spectrum of [NiII(PS2”)2]2 (3) in CD2Cl2. 32 Figure 2-4-1. ORTEP diagram of [PPh4][Co(PS2”)2]•CH3OH (4 •CH3OH) which has intramolecular pi-pi stacking from the phenyl group of different ligands shown with 35% thermal ellipsoids. H atoms, and solvated CH3OH are omitted for clarity. 35 Figure 2-4-2. ORTEP diagram of the metal center of [PPh4][Co(PS2”)2]•CH3OH (4 •CH3OH), showing a distorted octahedral geometry. 36 Figure 2-4-3. UV-vis-NIR spectrum of [PPh4][Co(PS2”)2] (4) in 0.073 mM CH3CN. 37 Figure 2-4-4. The ESI-MS spectrum of [Co(PS2”)2]- (the anion of 4) in negative mode. 38 Figure 2-4-5. The isotope spectrum of [Co(PS2”)2] - (the anion of 4) in negative mode. ( A is experiment value and B is calculated value ) 38 Figure 2-4-6. The 1H NMR spectrum of [PPh4][Co(PS2”)2] (4) in CD2Cl2. Inset: The 1H NMR spectrum range at 6.4-8.0 ppm.. 39 Figure 2-4-7. The 31P NMR spectrum of [PPh4][Co(PS2”)2] (4) in CD2Cl2. 40 Figure 2-4-8. The cyclic voltammogram of [PPh4][Co(PS2”)2] (4) at range 1.2V to -2.8V in CH3CN solution (scan rate :0.1Vs-1). 41 Figure 2-4-9. The cyclic voltammogram of [PPh4][Co(PS2”)2] (4) at range 1.2V to -2.4V in CH3CN solution (scan rate :0.1Vs-1). 41 Figure 2-4-10. The cyclic voltammogram of [PPh4][Co(PS2”)2] (4) at range 1.2V to -2V in CH3CN solution (scan rate :0.1Vs-1). 42 Figure 2-4-11. The irreversible CoIII/CoIV or CoIII-thiolate/CoIII-thiyl radical process in CH3CN solution. 42 Figure 2-5-1. Position of hydrogen and oxygen in GC. 43 Figure 2-5-2. 0.005mmole [NiII(PSSH”)2] (1) dissolved in 5mL tetrahydrofuran. 44 Figure 2-5-3. 0.005mmole [NiII(PSSH”)2] (1) dissolved in 5mL dichloromethane. 44 Figure 2-5-4. Variation of ESI-MS spectrum in negative mode of [NiII(PSSH”)2] (3) in CH2Cl2. (A): The experiment spectrum was complex 1 with irradiation and changed from complex 1 to complex 2. (B): The calculated spectrum was complex 2. (C): The calculated spectrum was complex 1. This spectrum major peak changed from 995.14 to 994.13 m/z. 45 Figure 2-5-5. The reaction of [NiII(PSSH”)2] (1) with irradiation to form [NiIV(PS2”)2] (2). The exact mass of complex 1 and complex 2 is 995.14 and 994.13 respectively. 46 Figure 2-5-6. The mechanism of [NiII(PSSH”)2] (1) with irradiation to form [NiIV(PS2”)2] (2). 46 Figure 3-1-1. The ideal cycle of [NiII(PSSH”)2] (1) and [NiIV(PS2”)2] (2) 47 Figure A-1. The 1H NMR spectrum of [PS2”]H2. 58 Figure A-2. The 31P NMR spectrum of [PS2”]H2. 58

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