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研究生: 普馬諾
Patil, Manoj Dnyanadev
論文名稱: 金金屬催化炔類轉化成高度官能化之碳環與雜環之途徑
Gold-Catalyzed Divergent Transformations of Alkyne into Highly Functionalized Carbo and Heterocycles
指導教授: 劉瑞雄
Liu, Rai-Shung
口試委員: 彭之皓
Peng, Chi-How
蔡易州
Tsai, Yi-Chou
李文泰
Li, Wen-Tai
侯敦仁
Hou, Duen-Ren
學位類別: 博士
Doctor
系所名稱: 理學院 - 化學系
Department of Chemistry
論文出版年: 2020
畢業學年度: 109
語文別: 英文
論文頁數: 483
中文關鍵詞: 金催化有機合成有機金屬化學催化劑金碳烯化學金碳烯
外文關鍵詞: Gold catalyst, Organic synthesis, Organometallic Synthesis, catalysis, carbene chemistry, gold carbene
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  • 本篇論文描述利用金金屬及銀金屬催化劑開發新型有機合成轉化方法,使用這些金屬能夠容易將基質在溫和、選擇性以及有效的條件下合成轉化成一系列雜環產物。為了使讀者容易理解,本篇論文將分成四個章節進行介紹。

    第一章內容包含從炔類、硝酮和親核試劑而得的金碳烯,條件下的曼尼希反應指出親核試劑控制了化學選擇性有著協同催化作用。而對於1-炔基-4-醇和2-乙炔基酚,在金催化氧化反應硝酮的情況下得到具同位選擇性的含氮二氫呋喃-3(2H)-酮,該反應機制涉及金碳烯和亞胺透過氧-氫-氮鍵結的曼尼希反應。而對於芳氧基乙炔來說,他們金烯醇選擇性的與硝酮反應生成3-亞烷基苯並呋喃-2-酮(由碳-氫-氧 氫鍵控制)。

    第二章內容包含由蒽氧基與芳氧基乙炔或是芳基炔丙基醚行一系列環化反應建構苯並呋喃[2,3-b]喹啉和6H-chromeno [3,4-b]喹啉骨架,這些雜環骨架雖然具有生物重要性但難以從現今文獻方法中得到,而本篇提及的策略藉由廣泛的基質被凸顯出來。而推測反應機制透過α-亞氨基金碳烯間體、氧芳基和苯甲醛之間的依序環化反應的機理。

    第三章內容包含由兩種不同的芳烴與金碳烯提供的三芳基甲烷的產物的金催化的氧化交叉偶聯反應組成。值得注意的是以磷酸作為助催化劑(10 mol%)在四氫呋喃溶液下可以有效抑制競爭性均相交聯反應。這些交叉偶聯反應具有廣泛適用的基質由吲哚,芳基胺和α-芳基重氮氰化物或酯類。我們的反應機理分析指出芳基苯胺的鹼度極大地影響了對交叉偶聯模的化學選擇性,並且還發現磷酸的存在增強了交叉偶聯效率,進一步為這種新的催化作用提供了機械學見解。

    第四章內容包含金催化三種分子由丙酸酯,呋喃和異噁唑的逐步環化而產生具取代基的吡咯,這些環化反應具有廣泛的基質應用以及產物吡咯存在於許多生物活性分子中。


    This dissertation describes development of new synthetic organic transformation using gold and silver catalysts. The use of these metals enable mild, selective and efficient transformation to give a range of heterocyclic products from readily available substrates. This thesis is divided into four chapters for ease of understanding.
    Chapter one is comprised of gold enolates from alkynes, nitrones and nucleophiles; their Mannich reactions manifest nucleophile-directed chemoselectivity to indicate a cooperative catalysis. For 1-alkyn-4-ols and 2-ethynylphenols, their gold-catalyzed nitrone oxidations afforded N-containing dihydrofuran-3(2H)-ones with syn-selectivity; the mechanism involves Mannich reactions of gold enolates with imines via an O-H--N bonding. For aryloxyethynes, their gold enolates react selectively with nitrones to deliver 3-alkylidenebenzofuran-2-ones, as controlled by a C-H--O hydrogen bonding.

    Chapter two is comprised of a facile annulation of anthranils with aryloxyethynes or aryl propargyl ethers to construct useful benzofuro[2,3-b]quinoline and 6H-chromeno[3,4-b]quinoline frameworks respectively; these heterocycles are not readily available from literature methods despite their biological significance. This high atom- and step-economy strategy is highlighted by a broad substrate scope. The reaction mechanism is proposed to proceed through sequential cyclizations among the oxyaryl group, gold carbene and benzaldehyde of the α-imino gold carbene intermediates.

    Chapter three is comprised of gold-catalyzed oxidative cross-coupling reactions of two distinct arenes with one gold carbene furnish triarylmethane products. Notably, competitive homo-coupling reactions are efficiently suppressed with a phosphoric acid as co-catalyst (10 mol %) in THF. These cross-coupling reactions have applicable substrates over a wide scope, with respect to indoles, arylamines and α-aryl diazo cyanides or esters. Our mechanistic analysis indicates that the basicity of the arylanilines greatly affects the chemoselectivity toward the cross-coupling mode. We discover also that the presence of a phosphoric acid enhances the cross-coupling efficiency, further providing mechanistic insight into this new catalysis.

    Chapter four is comprised of gold-catalyzed three component atom and step-economical annulations between propiolates, furans and isoxazoles to yield substituted pyrrole. These annulations were compatible with substrates over a wide scope. These resulting pyrroles are present in many bioactive molecules.

    CONTENTS Abstract III Acknowledgement VII Contents X List of Schemes XIII List of Tables XVI List of Figures XVI List of Publications XVIII Abbreviations XIX Chapter 1: Catalytic Transformations of Alkynes into either α-Alkoxy or α-Aryl Enolates: Mannich Reactions by Cooperative Catalysis and Evidence for Nucleophile-Directed Chemoselectivity. Introduction Result and Discussion 2 14 Conclusion 29 Experimental Procedure 29 Spectral Data 31 Reference 44 X-ray Crystallographic Data 47 1H and 13C NMR Spectra 55 Chapter 2: Direct Access to Benzofuro[2,3-b]quinoline and 6H-Chromeno [3,4-b]quinoline Cores through Gold-Catalyzed Annulation of Anthranils with Arenoxyethynes and Aryl propargyl ethers. Introduction Result and Discussion 104 114 Conclusion 130 Experimental Procedure 130 Spectral Data 133 Reference 149 X-ray Crystallographic Data 152 1H and 13C NMR Spectra 156 Chapter 3: Gold-catalyzed Oxidative Cross-coupling Reactions Among Two Distinct Arenes and One Gold Carbene with Phosphoric Acids as Cocatalysts Introduction Result and Discussion 231 240 Conclusion 261 Experimental Procedure 261 Spectral Data 265 Reference 285 X-ray Crystallographic Data 289 1H and 13C NMR Spectra 293 Chapter 4: Gold(I)-Catalysed Three-Component Reaction between Alkynes, Furans and Isoxazoles to Access Substituted Pyrroles Introduction Result and Discussion 374 386 Conclusion 405 Experimental Procedure 405 Spectral Data 406 Reference 424 X-ray Crystallographic Data 426 1H and 13C NMR Spectra 430 List of Schemes Chapter 1 Scheme 1: Generation of Gold carbenes from alkynes: A formalism to α-Carbene Gold carbene 4 Scheme 2: Common approaches to α-oxo gold carbenes from alkynes 5 Scheme 3: Intramolecular and intermolecular catalytic generation of a-oxo gold carbenes 6 Scheme 4: Rearrangement alkynyl sulfoxides catalyzed by gold(I) complexes. 7 Scheme 5: Synthesis of tetrahydrobenz[b]azepin-4-ones via intramolecular α- oxo gold carbenoid generation 7 Scheme 6: First example of accessing α-oxo gold carbenes via intermolecular oxidation of terminal alkynes 8 Scheme 7: Gold catalyzed synthesis of oxetan-3-ones from propargylic alcohols 8 Scheme 8: Gold-catalyzed [2+2+1] annulation of alkynes to synthesize 2,5 disubstituted oxazoles 9 Scheme 9: Oxidative cyclization of 1,5 enyne via 5-exo dig mode. 9 Scheme 10: Oxidative cyclization of 1,5 enyne via 5-endo dig mode 10 Scheme 11: oxidative annulation of homopropargyl alcohols with nitrone. 11 Scheme 12: Proposed reaction mechanism for Mannich-type addition 12 Scheme 13: General Mannich reaction and its mechanism 13 Scheme 14: Gold enolates with Mannich reaction. 14 Scheme 15: General synthetic procedure for synthesis of (ethynyloxy)benzene (1-1a) 17 Scheme 16: General synthetic procedure for synthesis of (prop-2-yn-1-yloxy)benzene (1-1h) 17 Scheme 17: General synthetic procedure for synthesis of nitrone (1-2a) 17 Scheme 18: Postulated reaction mechanism for gold-enolate enabled mannich reaction 26 Scheme 19: Postulated reaction mechanism 27 Chapter 2 Scheme 1: Gold-catalyzed [3+2] cycloaddition of ynamides with isoxazoles 106 Scheme 2: Gold-catalyzed [4+3]- and [4+2]-annulations of 3-en-1-ynamides with isoxazoles 107 Scheme 3: Gold catalyzed transfer of N-acylimino nitrenes to ynamides 107 Scheme 4: Gold-catalyzed C-H annulation of anthranils with alkynes 109 Scheme 5: Gold (III)-catalyzed annulation of N-benzyl ynamide and anthranil 110 Scheme 6: Gold (III)-catalyzed annulation reaction of N-furylmethylene ynamides and anthranils 111 Scheme 7: Gold-catalyzed annulations of N-aryl ynamides with Benzisoxazoles 112 Scheme 8: General synthetic procedure for synthesis of (ethynyloxy)benzene (1-1a). 117 Scheme 9: General synthetic procedure for synthesis of (prop-2-yn-1-yloxy)benzene (1-1h) 118 Scheme 10: Synthetic procedure of benzo[c]isoxazole (2-2a) 118 Scheme 11: A plausible mechanism 129 Chapter 3 Scheme 1: Formation of gold carbenes from diazo compounds 231 Scheme 2: Metal-mediated carbene transfer from diazo compounds 232 Scheme 3: General reactions of C-H activation and O-H insersion 233 Scheme 4: Palladium-catalyzed asymmetric O-H insertion 233 Scheme 5: Palladium-catalyzed asymmetric O-H insertion 234 Scheme 6: Ru-Catalyzed C2-Selective Functionalization of NH-Indole with diazo acetates 235 Scheme 7: Proposed Mechanisms for the construction of BIMs 236 Scheme 8: Proposed mechanism of the iridium/iminium co-catalyzed three-component reaction 237 Scheme 9: Plausible reaction mechanism of gold-catalyzed oxidative coupling 238 Scheme 10: Synthesis of N-methyl indole and N-phenyl indole 243 Scheme 11: Synthesis of 2-diazo-2-phenylacetonitrile 244 Scheme 12: Synthesis of N, N-dimethylaniline 245 Scheme 13: Cross-coupling reactions between two different anilines 253 Scheme 14: Chemical functionalization’s of cross-coupling products 254 Scheme 15: The role of anilines in cross-coupling reactions 258 Scheme 16: A postulated mechanism 259 Chapter 4 Scheme 1: Gold-catalyzed [3+2], [3+3] and [4+1] annulations 374 Scheme 2: Formalization of difference in N-oxide attack and O- and N-attack of isoxazoles on gold activated alkyne 375 Scheme 3: Enantioselective addition of nitroalkanes to isoxazoles 376 Scheme 4: Enantioselective cyclopropanation of styrylisoxazoles 377 Scheme 5: Asymmetric synthesis of dihydroxy-4-nitroisoxazolinones from isoxazoles 377 Scheme 6: Regioselective trifluoromethylation of 4-nitroisoxazoles. 378 Scheme 7: Rhodium-catalyzed [3+2] cycloaddition of triazole with isoxazole 379 Scheme 8: Rh-catalyzed ring opening reaction of isoxazoles with diazo compounds 380 Scheme 9: Rh-catalyzed ring expansion reaction of isoxazoles with vinyldiazo carboxylates to give 1,4-dihydropyridine 381 Scheme 10: Platinum-catalyzed formal [5+2]- and [4+2]-annulations of isoxazoles 382 Scheme 11: Gold-catalyzed [4+1]-annulation between 1,4-diyn-3-ols and isoxazoles 383 Scheme 12: Proposed mechanism for gold-catalyzed [4+1]-annulation between 1,4-diyn-3-ols and isoxazoles 384 Scheme 13: Annulations between propiolate derivatives and isoxazoles 385 Scheme 14: Gold(I)-Catalyzed Cyclization of Furans with Alkynes 387 Scheme 15: Synthetic procedure of tert-butyl 3-phenyl propiolate (4-1a) 380 Scheme 16: Synthetic procedure of tert-butyl 3-phenyl propiolate (4-1a) 382 Scheme 17: Synthetic procedure of 1,3-diphenylprop-2-yn-1-one (4-2c) 382 Scheme 18: Synthetic procedure of 2,5-diphenylfuran (4-2e) 382 Scheme 19: Synthetic procedure of 3,5-dimethylisoxazole (4-3b) 382 Scheme 20: Synthetic procedure of 3-methyl isoxazole (4-3b) 383 Scheme 21: Effect of nucleophilicity of furans 399 Scheme 22: Effect of nucleophilicity of Isoxazoles 400 Scheme 23: Effect of bulky furan and rate of reaction 402 Scheme 24: A postulated mechanism 403 List of Tables Chapter 1 Table 1: Reactions of phenoxyethyne 1-1a with nitrone 1-2a over gold catalysts 15 Table 2: Catalytic Reactions on phenoxyethyne 1-1a-g 18 Table 3: Gold-catalyzed reactions of various nitrones 1-2b-k 21 Table 4: Gold-catalyzed reactions of various phenyl propargyl ethers and nitrones 24 Chapter 2 Table 1: Catalytic Annulations with various gold catalysts 115 Table 2: Catalytic Annulations with various phenoxyethyne 119 Table 3: Catalytic Annulations with various benzoisoxazole 119 Table 4: Annulations of various aryl propargyl ethers 125 Table 5: Catalytic Annulations with various benzoisoxazole with propargyl ether 127 Chapter 3 Table 1: Cross-coupling reactions under various conditions 241 Table 2: Oxidative coupling reactions with various indoles 246 Table 3: Cross-coupling reactions with α-diazo species Table 4: Cross-coupling reactions with various anilines 249 251 Chapter 4 Table 1: Optimization of reaction condition 389 Table 2: Gold-catalyzed annulation with various propiolates 394 Table 3: Gold-catalyzed annulation with various furans 497 List of Figures Chapter 1 Figure 1: Singlet and triplet carbenes 3 Figure 2: Fischer and schrock carbenes 3 Figure 3: List of substrates 16 Figure 4: ORTEP diagram of compound 1-4d and 1-5a 28 Chapter 2 Figure 1: The general retrosynthetic basis for the synthesis of diverse N-heterocycles 104 Figure 2: Selective bioactive natural alkaloids 114 Figure 3: List of substrates Figure 4: ORTEP diagram of compounds 2-3a and 2-6l 117 130 Chapter 3 Figure 1: Classification of carbene precursors 233 Figure 2: List of substrates 243 Figure 3: ORTEP diagram of compounds (3-4b) and (3-4’’) 261 Chapter 4 Figure 1: List of substrates 391 Figure 2: ORTEP diagram of compounds (4-4f) and (4-5d’) 404

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    19. For a 1,5-acyl shift, see: a) Rao, W.; Koh, M.; Kothandaraman, J. P.; Chan, P. W. H. J. Am. Chem. Soc. 2012, 134, 10811; b) Leboeuf, D.; Simonneau, A.; Aubert, C.; Malacria, M.; Gandon, V.; Fensterbank, L. Angew. Chem. Int. Ed. 2011, 50, 6868; c) Rao, W.; Koh, M. J.; Chan, P. W. H. J. Org. Chem. 2013, 78, 3183.
    20. Huguet, N.; Leboeuf, D.; Echavarren, A. M. Chem. Eur. J. 2013, 19, 6581.
    21. a) Huple, D. B.; Ghorpade, S.; Liu, R.-S. Adv. Synth. Catal. 2016, 358, 1348; b) Dorel, R.; Echavarren, A. M. Chem. Rev. 2015, 115, 9028; c) Llpez, F.; MascareÇas, J. L.; Beilstein, J. Org. Chem. 2011, 7, 1075; d) Hashmi, A. S. K. Chem. Rev. 2007, 107, 3180.
    22. Hashmi, A. S. K.; Carmen Blanco, M.; Kurpejovic, E.; Frey, W.; Bats, J. W. Adv. Synth. Catal. 2006, 348, 709.
    23. Crystallographic data of compound 3-4b and 3-4’’ was deposited in Cambridge Crystallographic Data Centre: (3-4b)-CCDC: 2009271, (3-4’’)-CCDC: 2009271.
    24. Karad, S. N.; Chung, W.-K. and Liu, R.-S. Chem. Commun., 2015, 51, 13004.
    25. Kitamura, C.; Abe, Y.; Ohara, T.; Yoneda, A.; Kawase, T.; Kobayashi, T.; Naito, H.; Komatsu, T.; Chem. Eur. J., 2010, 16, 890.
    26. Griesbeck, A. G.; Franke, M.; Neudorfl, J.; Kotaka, H. Beilstein J. Org. Chem. 2011, 7, 127.

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