(4 + 3) Annulation of Enone-Tethered Indoles with α-Alkylidene Succinimides: Access to Seven-Membered Azepino[3,2,1-hi]Indole Scaffolds

Abstract

We have developed a straightforward synthesis of azepino[3,2,1-hi]indole architectures having four contiguous chiral carbons as single diastereomers. This metal-free protocol between indole-enones and alkylidene succinimides proceeds efficiently under ambient conditions, demonstrating a broad scope in good to excellent yields. The feasibility of the current methodology was illustrated by one-pot, gram-scale synthesis and further modifications.