I2‐Promoted sp3 C−H Oxidation/Annulation Sequences for the Synthesis of Indoloquinolines from 2‐(1H‐indol‐2‐yl)anilines and Aryl Methyl Ketones

Abstract An iodine/DMSO‐promoted approach has been developed for the synthesis of indoloquinolines via a sequential sp 3 C−H oxidation/intramolecular cyclization using 2‐(1 H ‐indol‐2‐yl)anilines and aryl methyl ketones. A wide range of aryl methyl ketones, including drugs and complex bioactive molecule‐derived substrates were compatible in the present reaction with yields in the range of 30–96%. This protocol proceeds through sp 3 C−H oxidation of aryl methyl ketones to phenylglyoxals, subsequent imine formation, and cyclization to furnish the indoloquinolines. Further, the reaction is applicable for gram‐scale synthesis and is operationally simple.