Iodo-Cycloisomerization of Aryl(indol-3-yl)methane-Tethered Propargyl Alcohols to 3‑Iodocarbazoles via Selective 1,2-Alkyl Migration

Herein, we disclose the first report on iodo-cycloisomerization of 1-(indol-3-yl)-1-arylbut-3-yn-2-ols to form 3-iodocarbazoles. The synthesis proceeds through a cascade 5-endo-spirocyclization, followed by selective 1,2-alkyl migration. This method governs the green synthesis principles such as open-flask reaction, AcOEt as the solvent, rt reaction with short time, use of iodine, and broad substrate scope with atom and step economy.