Visible-Light-Induced, Catalyst-Free Monofluoromethyl Sulfonylation of Alkenes with Iodine(III) Reagent and DABSO.

A visible-light-induced radical relay strategy to access heterocycles bearing a monofluoromethylsufonyl moiety is reported, with PhI(OCOCHF) as the CHF radical precursor and DABSO as the SO source. A range of oxindoles, containing a CHFSOCH- group at the C3 position, were synthesized from -arylacrylamides in up to 97% yields. The protocol features catalyst-free photochemical tandem, mild reaction conditions, broad functional group compatibility, and good to excellent yields.