4‐Dimethylaminopyridine‐Boryl Radical Promoted Monodefluorinative Alkylation of 3,3‐Difluorooxindoles

Comprehensive Summary A selective monodefluorinative alkylation of 3,3‐difluorooxindoles is achieved. The reaction starts by the attack of a 4‐dimethylaminopyrine‐boryl radical to the carbonyl oxygen atom of 3,3‐difluorooxindoles, followed by a spin‐center shift to generate radical intermediates with the elimination of a fluoride anion. The subsequent radical addition to alkenes affords a range of 3‐alkyl‐fluorooxindoles products. The strategy offers access to C‐3 functionalized oxindoles with wide substrate scope and tolerates a wide range of functional groups.