Photoredox-Catalyzed Sulfonaminoformyloxylation of Alkenes with N-Aminopyridinium Salts and DMF

A photoredox-catalyzed three-component sulfonaminoformyloxylation reaction between alkenes, N-aminopyridinium salts and DMF has been developed, which avoids the usage of erosive formic acid as the formyloxylation reagent. Besides DMF, alkyl and aryl carboxylic acids proved to be feasible nucleophiles to afford various beta-amino esters. The robustness of this method was further demonstrated by its applicability in the late-stage modification of biological molecules. Control experiments suggested that a sulfonamidyl radical was involved in this reaction.