Pyrone Diels-Alder Routes to Indolines and Hydroindolines: Syntheses of Gracilamine, Mesembrine, and Δ<sup>7</sup>-Mesembrenone
作者:Pei Gan、Myles W. Smith、Nathaniel R. Braffman、Scott A. Snyder
DOI:10.1002/anie.201510520
日期:2016.3.7
Although the Diels–Alder reaction has long been utilized for the preparation of numerous heterocycles, opportunities to extend its power remain. Herein, we detail a simple, modular, and robust approach that combines various amines regioselectively with 4,6‐dichloropyrone to create substrates which, under appropriate conditions, can directly deliver varied indolines and hydroindolines through [4+2]
尽管Diels-Alder反应早已被用于制备众多杂环,但仍有扩大其功率的机会。本文中,我们详细介绍了一种简单,模块化且可靠的方法,该方法将多种胺与4,6-二氯吡喃区域选择性地结合在一起,以形成底物,这些底物在适当的条件下可以通过[4 + 2]环加成直接递送各种二氢吲哚和氢二氢吲哚,但取代模式很困难。否则访问。作为该策略力量的初步证明,已正式或通过直接全合成获得了几种不同的天然产物,并努力开发其中一种(复杂的芳科植物生物碱gracilamine),从而以线性步长提供了迄今为止最短的途径数数。