Metal Free Benzylation and Alkylation of Quinoxalin‐2(1H)‐ones with Alkenes Triggered by Sulfonyl Radical Generated from Sulfinic Acids

Abstract A metal‐free domino multicomponent reaction for the direct C−H benzylation and alkylation of quinoxalin‐2(1H)‐ones using alkenes is described. Triggered by the sulfonyl radical generated from sulfinic acid, the alkenes are transformed to alkyl radicals that react exclusively at the C‐3 position of quinoxalin‐2(1H)‐ones. Importantly, the method not only functionalizes medicinally important quinoxalin‐2(1H)‐one scaffold, but also furnishes diverse medicinally relevant sulfones in good to excellent yields under mild conditions. magnified image