本篇描述了使用金或膦催化劑開發新的合成有機機轉。文中所使用的金屬使容易取得之反應物以溫和且具選擇性的和有效地轉化為具廣泛運用的含氮、氧和硫的複雜有機分子。為了更好地理解，本文分為四個章節。第一章描述了通過 α-重氮腈與環丙烯衍生物，以具立體選擇性金催化合成高度取代的 (E)-2,3-二氮雜-1,3,5-己三烯；此類產物源自於α-芳基重氮腈對乙烯基金金屬碳烯的非典型重氮攻擊。我們也報告了這些 2,3-二氮雜-1,3,5-己三烯衍生物的新型陰離子環化的發展，產生各種含二氮雜的雙環化合物，例如1H-吡唑並[4,3-b]吡啶-5-酮。第二章，使用金金屬和膦催化劑的非對稱二芳基乙烯酮與硫代炔的二次催化環化。本章利用 α-芳基重氮酮生成金 π-烯酮 (gold π-ketenes)，最終生成薁-1-酮 (azulen-1-one) 衍生物。令人驚訝的是，使用相同的反應物，三(五氟苯基)膦 (P(C6F5)3) 催化劑在甲苯溶液中加熱提供了高度取代的 1-萘酚 (1-naphthols)，具有驚人的區域選擇性 (regioselectivity)； 當中只有一個特定的苯環參與苯並環化。 這種完整的區域選擇性對於典型的史密斯-霍恩 (Smith–Hoehn) 反應來說是前所未見的。第三章，分別使用金催化和膦添加劑進行 α-芳基重氮酮與 1,3-二苯基環戊二烯反應的兩種不同化學選擇性。在添加金催化劑後，α-芳基重氮酮最初會形成金碳烯，爾後金碳烯被 1,3-二取代環戊二烯給捕捉，進而得到 C-H 插入反應之產物。在三(五氟苯基)膦添加劑作用下，α-芳基重氮酮在高溫下形成二芳基乙烯酮，並透過三(五氟苯基)膦進一步穩定以確保其構型穩定，然後進行前所未有的[4C + 2C ] 環加成反應。最後第四章開發一種新途徑，是用於金催化2-氰甲基-1-乙炔基苯 (2-cyanomethyl-1-ethynylbenzene) 與苯並異噁唑 (benzisoxazoles) 的C-H 成環/鹼促進環化反應，逐步構建成苯並[7,8]吲嗪基[2,3,4,5- ija]喹唑啉 (benzo[7,8]indolizino [2,3,4,5-ija]quinazoline) 骨架。本篇在較高溫度下進行了一鍋化反應，建構了多重稠合之含氮雜環 (N-heterocycles)，此類含氮雜環廣泛存在於多種天然物、生物活性合成藥物和電子材料中。本反應可使用的反應物之範圍非常廣泛，反應條件可以承受多種不同官能基，這進一步增強了此方法的合成影響力。

The development of novel synthetic organic transformations utilizing gold and phophine catalysts is discussed in this dissertation. Use of these metals enables the delicate, methodical, and efficient synthesis of numerous heterocyclic and carbocyclic compounds from a wide range of readily accessible substrates. To facilitate comprehension, this dissertation is divided into four chapters.
The first chapter comprised of gold-catalyzed stereoselective synthesis of highly substituted E-configured 2,3-diaza-1,3,5-hexatrienes using α-diazo nitriles and cyclopropene derivatives; such products arise from an atypical diazo attack of α-aryldiazo nitriles at vinylgold carbenes. We also report the development of new anionic cyclizations for the derivatives of these 2,3-diaza-1,3,5-hexatrienes, yielding various diazacontaining bicyclic compounds such as 1H-pyrazolo[4,3-b]pyridine-5-ones.
The second chapter comprised of two catalytic annulations of non-symmetric diarylketenes with thioalkynes using gold and phosphine catalysts respectively. We employed α-aryldiazo ketones to generate gold π-ketenes, ultimately yielding azulen-1-one derivatives. Surprisingly, with the same substrates, P(C6F5)3 catalyst afforded highly substituted 1-naphthols in hot toluene with astonishing regioselectivity; only one specific benzene ring participated in the benzannulation. This complete regioselectivity is unprecedented for typical Smith–Hoehn reactions.
The third chapter comprised of two distinct reaction chemoselectivities for the reactions of α-aryldiazo ketone with 1,3-diphenylcyclopentadiene using gold catalyst and phosphine additives, respectively. In the presence of gold catalyst, α-aryldiazo ketone forms gold carbenes initially that are trapped with this 1,3-disubstituted cyclopentadiene to afford C−H insertion products. In the presence of P(C6F5)3 additive, α-aryldiazo ketone forms diarylketenes initially at elevated temperature, which were further stabilized by P(C6F5)3 to secure their entity before proceeding to unprecedented [4C + 2C] cycloadditions.
The fourth chapter comprised of development of a relay catalysis between 5-cyano-3-en-1-ynes with anthranils to yield benzo[7,8]indolizino[2,3,4,5-ija]quinazoline derivatives. Such a novel heteroaromatic synthesis is conducted with one-pot and two-step operation, involving initial formation of 7-formylindole intermediates that can be implemented by DBU to activate a novel indole-nitrile-aldehyde cyclization. Our control experiments reveal that 2-substituted 7-formylindole intermediates from the initial alkyne C(α)-addition is applicable to this DBU-induced three component cyclization whereas 3-substituted 7-formylindole intermediates from the initial alkyne C(β)-addition is inactive towards this DBU reaction.

Table of content

Chapter 1: Gold-Catalyzed Synthesis of Diaza-hexatrienes Via Diazo Attack at Vinylgold Carbenes: An Easy Access to 1H-Pyrazolo[4,3-b]pyridine-5-ones

Introduction 02
Results and Discussion 17
Conclusion 33
Experimental Section 33
Spectral Data 38
1H NOE of Compound 58
References 71
X-ray Crystallographic Data 77
1H and 13C NMR Spectra 82

Chapter 2: Reactions of Thioalkynes with Diarylketenes via [3+2]-Annulation Versus Benzannulation using Au and P(C6F5)3 Catalysts

Introduction 218
Results and Discussion 227
Conclusion 241
Experimental Section 241
Spectral Data 244
1H NOE of Compound 259
References 260
X-ray Crystallographic Data 263
Computational Details 265
1H and 13C NMR Spectra 300

Chapter 3: Reactions of 1,3-Diphenyl Cyclopentadiene with α-Aryldiazo ketones to Enable C-H insertions versus [4+2]-cycloadditions via Au catalyst and P(C6F5)3 Additive Respectively

Introduction 371
Results and Discussion 380
Conclusion 396
Experimental Section 396
Spectral Data 403
1H NOE of Compound 429
References 429
X-ray Crystallographic Data 433
1H and 13C NMR Spectra 444

Chapter 4: One Pot Synthesis of Two Nitrogen-Containing Polyaromatic Compounds through Relay Gold Catalysis and DBU-Promoted Cyclizations

Introduction 562
Results and Discussion 574
Conclusion 588
Experimental Section 588
Spectral Data 597
References 615
X-ray Crystallographic Data 619
1H and 13C NMR Spectra 633

Chapter 1
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Chapter 2
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40. For X-ray diffraction studies of key compounds: (a) 2-4b: CCDC-2074288. (b) 2-5a: CCDC- 2108140.
41. Phosphine is known to catalyze [2+2]-cycloadditions of ketenes with imines. See selected examples: (a) S. Chen, E. C. Salo, K. A. Wheeler, N. J. Kerrigan. Org. Lett. 2012, 14, 1784-1787. (b) B. L. Hodous, G. C. Fu, J. Am. Chem. Soc. 2002, 124, 1578-1579.
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43. (a) Y. Zheng, J. Zhang, X. Cheng, X. Xu and L. Zhang, Angew. Chem., Int. Ed., 2019, 58, 5241–5245. (b) P. Sharma, R. R. Singh, S. S. Giri, L. Y. Chen, M. J. Cheng and R. S. Liu, Org. Lett., 2019, 21,5475–5479.
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45. (a) Xu, B.; Zhu, S. F.; Zuo, X. D.; Zhang, Z. C.; Zhou, Q. L. Angew. Chem. Int. Ed. 2014, 53, 3913-3916. b) Chen, C. N.; Cheng, W. M.; Wang, J. K.; Chao, T. H.; Cheng, M. J.; Liu, R. S. Angew. Chem. Int. Ed., 2021, 60, 4479-4448.
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Chapter 3
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Chapter 4
1. General reviews on preparation of nitrogen-heterocycles: (a) “Amino-Based Building Blocks for the Construction of Biomolecules”: A. Mann in Amino Group Chemistry: From Synthesis to the Life Sciences (Ed.: A. Ricci), Wiley-VCH, Weinheim, 2007, pp. 207-256-592 (b) Balasubramanian, M.; Keay, J. G. in Comprehensive Heterocyclic Chemistry (Eds.: A. R. Katritzky, C. W. Rees), Pergamon, Oxford, 1984, pp. 245-300 (c) Jin, Z. Nat. Prod. Rep. 2011, 28, 1143-1191. (d) Amines: Synthesis, Properties and Applications (Ed.: S. A. Lawrence),
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