Stereoselective Double Spirocyclization of 2-Benzyl-3-alkynyl Chromone with Nitrone via Gold-Catalyzed Cascade Reactions
作者:Amit Vijay Sasane、Chun-Tang Chiou、Ming-Yiang Chang、Wen-Tai Li
DOI:10.1021/acs.orglett.4c02338
日期:2024.8.9
A novel, highly stereoselective gold-catalyzed spirocyclization of 2-benzyl-3-alkynyl chromone with nitrone is described. This cascade reaction involves gold-catalyzedcycloisomerization, nitrone-olefin [3 + 2]-annulation, alkene oxidation, and rearrangement for the formation of spirocyclic products. Interestingly, the isoxazolidine ring generated from [3 + 2]-annulation donates oxygen to alkene to
描述了一种新型的、高度立体选择性的金催化 2-苄基-3-炔基色酮与硝酮的螺环化反应。该级联反应涉及金催化的环异构化、硝酮-烯烃[3+2]-成环、烯烃氧化以及形成螺环产物的重排。有趣的是,由[3 + 2]-环化生成的异恶唑烷环将氧提供给烯烃,生成新的吡喃-3(4 H )-酮和氮杂环丁烷环,在加热时形成二螺-苯并呋喃。这项工作展示了金催化的一锅多步反应,反应温度直接影响螺环产物的形成。