Transition Metal-Free Iodine-Catalyzed Denitrative C–S Cross-Coupling: An Atypical Route to Access Thiochromane Derivatives
Anuradha Nandy, Govindasamy Sekar
Abstract
An iodine-catalyzed denitrative C-S cross-coupling reaction has been developed to attain thiochromanones from 2'-nitrochalcones and xanthate. The strategy was extended for a three-component synthesis of thiochromenes via intermolecular C-S cross-coupling followed by aldol reaction. The reaction proceeds via activation of the keto group of chalcone through a halogen bond complex with iodine/denitrative C-S bond formation with xanthate/sulfa-Michael addition to chalcones. The methodology was also demonstrated for chemoselective reduction of chalcones. The protocol was also employed to synthesize biologically important 3'-hydroxythioflavone and thiochromenones.
Topics & Concepts
ChemistryXanthateCatalysisIodineAldol reactionCoupling reactionChalconeIntermolecular forceTransition metalHalogenCombinatorial chemistryMedicinal chemistryPolymer chemistryStereochemistryOrganic chemistryMoleculeAlkylSulfur-Based Synthesis TechniquesChemical Synthesis and ReactionsSynthesis of Indole Derivatives