Department of Chemistry, University of California, Irvine, CA, 92697-2025, USA.
Departments of Chemistry and of Molecular Biology & Biochemistry, University of California, Irvine, CA, 92697-2025, USA.
Angew Chem Int Ed Engl. 2017 Aug 21;56(35):10525-10529. doi: 10.1002/anie.201704119. Epub 2017 Jul 21.
The ubiquitous use of π-rich five-membered heterocycles has driven the development of new methods for their synthesis for more than a century. Here, we disclose a general and reliable reaction manifold for the construction of highly substituted heterocycles through a facile Lewis-acid-catalyzed oxetane rearrangement. Notably, this methodology employs a keto-oxetane motif as a 1,4-dicarbonyl surrogate, which can be synthesized using robust alkylation or alkenylation reactions, and thus obviates the need to access 1,4-dicarbonyl compounds via umpoled starting materials. We harnessed this reactivity to generate a broad range of substituted furans and pyrroles, and extended this methodology to produce benzo-fused versions thereof.
富含π的五元杂环的广泛应用促使人们在一个多世纪的时间里开发出了许多新的合成方法。在这里，我们公开了一种通用且可靠的反应模式，通过简便的路易斯酸催化的环氧乙烷重排反应来构建高度取代的杂环。值得注意的是，该方法采用酮-环氧乙烷作为 1,4-二羰基的替代物，该替代物可以通过稳定的烷基化或烯丙基化反应合成，因此无需通过非极性起始原料来获得 1,4-二羰基化合物。我们利用这种反应性生成了广泛的取代呋喃和吡咯，并将该方法扩展到了苯并稠合杂环的合成中。
