K2S2O8/TFA-mediated [3+2+1] synthesis of substituted quinolines from anilines and alcohols using DMSO as a C1 source

Abstract

An efficient K₂S₂O₈/TFA-mediated [3+2+1] cycloadditions of readily available anilines, primary alcohols/secondary alcohols, and DMSO is described. This method allows the direct and highly effective synthesis of privileged quinolones, such as 3-arylquinolines and 4-arylquinolines, with exclusive regioselectivity and good functional group tolerance in good to excellent yield. DMSO is employed as the C1 building block of quinoline products, the oxidant, and the solvent. The possible reaction mechanism is also discussed. The method can also be extended to a gram scale.