Visible‐Light‐Induced Aerobic Intramolecular Cyclization of (2‐Aminophenyl)(1<i>H</i>‐indol‐1‐yl)methanones: Direct Access to Bioactive Tryptanthrin and its Derivatives
Mariyaraj Arockiaraj, Gargi Singh, Sasi Sree Marupalli, Venkatachalam Rajeshkumar
Abstract
Abstract Visible‐light‐induced mild, transition metal, base, and photocatalyst‐free green protocol has been developed for the synthesis of tryptanthrin and its derivatives. The present reaction is compatible with a wide range of substrates with good to high yields. Further, a novel synthetic transformation of tryptanthrin derivatives has been achieved by the decarboxylative addition of cyanoacetic acid for the first time. This reaction proceeds by visible‐light‐induced single electron transfer between the substrate and oxygen, followed by intramolecular cyclization without the use of an external photocatalyst. magnified image
Topics & Concepts
ChemistryIntramolecular forceVisible spectrumCyanoacetic acidPhotochemistryPhotocatalysisSubstrate (aquarium)Electron transferCombinatorial chemistryOrganic chemistryCatalysisOceanographyGeologyPhysicsOptoelectronicsRadical Photochemical ReactionsCatalytic C–H Functionalization MethodsPhenothiazines and Benzothiazines Synthesis and Activities