Synthesis of 3-SCF<sub>2</sub>H-/3-SCF<sub>3</sub>-chromones via Interrupted Pummerer Reaction/Intramolecular Cyclization Mediated by Difluoromethyl or Trifluoromethyl Sulfoxide and Tf<sub>2</sub>O
Xuemin Li, Yue Li, Jingyue Yang, Haofeng Shi, Zhenkang Ai, Han Chi, Jiaxin He, Yunfei Du
Abstract
The reaction of alkynyl aryl ketones bearing an o-methoxy group with difluoromethyl sulfoxide in the presence of Tf2O was found to conveniently afford the corresponding 3-SCF2H-substituted chromones. The combining use of difluoromethyl sulfoxide/Tf2O could represent the first reagents system that can introduce the biologically important SCF2H moiety under base-free conditions via an interrupted Pummerer reaction. The same protocol could also be applied to the synthesis of 3-SCF3-substituted chromones by replacing difluoromethyl sulfoxide with trifluoromethyl sulfoxide and CH3CN with toluene.
Topics & Concepts
ChemistrySulfoxideTrifluoromethylMoietyArylIntramolecular forceReagentPummerer rearrangementMedicinal chemistryDimethyl sulfoxideOrganic chemistryStereochemistryCatalysisAlkylAcetic anhydrideFluorine in Organic ChemistrySulfur-Based Synthesis TechniquesRadical Photochemical Reactions