Recent Developments in the Cyclization of Alkynes and Nitrogen Compounds for the Synthesis of Indole Derivatives

This review is intended to highlight the most useful approaches for the synthesis of indole derivatives (azaindoles, carbazoles, carbolines, indazoles, 3 H ‐indoles, indolines, indolizines, isoindoles, and isoindolines), which were described by using transition‐metal catalyzed cyclization reactions of alkynes and nitrogen compounds. The methodologies carried out under metal‐free conditions will also be illustrated herein. This review will cover the data published mostly in the past decade.