Phosphine‐Catalyzed Enantioselective Dearomative [3+2]‐Cycloaddition of 3‐Nitroindoles and 2‐Nitrobenzofurans
作者:Huamin Wang、Junyou Zhang、Youshao Tu、Junliang Zhang
DOI:10.1002/anie.201900036
日期:2019.4.8
dearomative cycloaddition of 3‐nitroindoles and 2‐nitrobenzofurans have emerged as a powerful protocol to construct chiral fused heterocyclic rings. However, organocatalytic dearomative reaction of these two classes of heteroarenes has become a long‐standing challenging task. Herein, we report the first example of phosphine‐catalyzed asymmetric dearomative [3+2]‐cycloadditio of 3‐nitroindoles and 2‐nitrobenzofurans
在过去的几年中,金属催化的3-硝基吲哚和2-硝基苯并呋喃的脱芳香环化反应已经成为构建手性稠合杂环的有效方法。然而,这两类杂芳烃的有机催化脱芳香反应已成为一项长期的挑战性任务。本文中,我们报道了第一个由膦催化的3-硝基吲哚和2-硝基苯并呋喃的不对称脱芳香性[3 + 2]-环加成的例子,它们为合成手性2,3-稠合的环戊环戊二烯提供了新的,简便而有效的方法吲哚啉和二氢苯并呋喃,分别通过脱芳香性[3 + 2]-环加成反应与烯丙酸酯和MBH碳酸酯反应。