Lewis Acid-Catalyzed 2,3-Dihydrofuran Acetal Ring-Opening Benzannulations toward Functionalized 1-Hydroxycarbazoles
作者:Shaoren Yuan、Gabriel Guerra Faura、Hailey E. Areheart、Natalie E. Peulen、Stefan France
DOI:10.3390/molecules27238344
日期:——
of a Lewis acid-catalyzed, intramolecular ring-opening benzannulation of 5-(indolyl)2,3-dihydrofuran acetals is described. The resulting 1-hydroxycarbazole-2-carboxylates are formed in up to 90% yield in 1 h. The dihydrofuran acetals are readily accessed from the reactions of enol ethers and α-diazo-β-indolyl-β-ketoesters. To highlight the method's synthetic utility, a formal total synthesis of murrayafoline
描述了路易斯酸催化的 5-(吲哚基)2,3-二氢呋喃缩醛的分子内开环苯并环化的发展。生成的 1-hydroxycarbazole-2-carboxylates 在 1 小时内以高达 90% 的产率形成。二氢呋喃缩醛很容易从烯醇醚和 α-重氮-β-吲哚基-β-酮酯的反应中获得。为了突出该方法的合成效用,进行了 murrayafoline A 的正式全合成,murrayafoline A 是一种具有生物活性的含咔唑天然产物。