Visible Light-Driven\nInterrupted Barton Reaction:\nIntermolecular Radical-Relay Sulfonyloximation of Alkenes with DABSO\nand Alkyl Nitrites

A visible light-driven, intermolecular interrupted Barton\nreaction\nhas been developed for radical-relay sulfonyloximation of alkenes\nwith alkyl nitrites, using DABSO as a trapping reagent. This method\novercomes the challenges of competing normal Barton reactions and\npolarity mismatches by rapidly and irreversibly capturing alkyl radicals,\npreventing unwanted side reactions. The resulting polarity-reversed\nsulfonyl radicals undergo highly selective addition to alkenes, yielding\nα-alkylsulfonyl ketoximes tethered to hydroxyl or ketone groups.\nConducted under mild visible light conditions, this approach eliminates\nthe need for harsh mercury lamps, offering a scalable, chemoselective\nmethod for synthesizing valuable sulfonylated oxime derivatives.