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| 題名: | 銀介導溶劑控制下從5-溴-1,2,3-三嗪選擇性合成呋喃以及吡咯;Silver-Mediated Divergent Synthesis of Furans and Pyrroles from 5-Bromo-1,2,3-Triazine by Solvent Control |
| 作者: | 陳湘文;Chen, Hsiang-Wen |
| 貢獻者: | 化學學系 |
| 關鍵詞: | 烯炔;環化異構化反應;三嗪;呋喃;吡咯;Enynes;Cycloisomerization;Triazines;Furans;Pyrroles |
| 日期: | 2024-08-21 |
| 上傳時間: | 2024-10-09 15:28:35 (UTC+8) |
| 出版者: | 國立中央大學 |
| 摘要: | 烯炔類分子的環化異構化反應是一種經常用來合成五員雜環化合物的途徑之一，該途徑符合原子經濟的要求。我們旨在開發藉由單一起始物選擇性合成呋喃以及吡咯的方法。傳統合成方法在進行此類反應時，需要過渡金屬催化對多重鍵進行活化，合成特定含有酮基或胺基的前驅物，從中促使酮基或胺基攻打多重鍵進行環化異構化反應，建構呋喃或吡咯骨架。本論文中，我們則是藉由5-炔基取代-1,2,3-三嗪作為起始物，選擇適當的溶劑及親核試劑，藉由銀介導親核性開環反應形成含烯炔官能基的中間體，有效控制合環反應的選擇性，同時得到相對應的產物。研究結果顯示，當反應溶劑四氫呋喃中含水時，5-取代呋喃-3-醛則是主要的產物；而當反應溶劑僅使用四氫呋喃，並以二乙胺作為親核試劑時，則有效促使反應趨向產生5-取代吡咯-3-醛。該反應不需要使用昂貴的試劑，只需使用硝酸銀或醋酸銀來促進反應，使得兩種產物均可分別得到良好到優異的產率及化學選擇性。該方法同時展示反應物的多樣性、簡易的實驗操作和原子經濟性等優點。;The cycloisomerization reaction of enynes is a commonly employed synthetic route for the synthesis of five-membered heterocycles that meets the requirements of atom economy. Herein, we aim to develop a method to selectively synthesize furans and pyrroles from a single starting material. Traditional synthetic methods for such cycloisomerization reactions often use a specific starting material containing ketone or amine groups as precursors, which promotes the attack of multiple bonds by ketone or amine groups to undergo transition metal-catalyzed cyclization isomerization reactions, resulting in the construction of furan or pyrrole skeletons, respectively. In this thesis, we employed 5-substituted-1,2,3-triazine as the starting material and chose a suitable solvent and nucleophilic reagent, forming an intermediate with an alkyne functional group through silver-mediated nucleophilic ring-opening reactions. The selectivity of the cyclization reaction was effectively controlled, and the corresponding furan and pyrrole products were obtained. Our findings show that when the reaction is in aqueous tetrahydrofuran, 5-substituted furan-3-aldehyde is the major product, while using tetrahydrofuran as the reaction solvent and diethylamine as the nucleophilic reagent effectively promotes the production of 5-substituted pyrrole-3-aldehyde. This reaction does not require expensive reagents, only silver nitrate or silver acetate to promote the reaction, allowing both products to be obtained with good to excellent yields and chemoselectivity. This approach has advantages in terms of substrate scope, user-friendly procedures, and atom economy. |
| 顯示於類別: | [化學研究所] 博碩士論文
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