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]