Direct Fluorosulfonamidation of (Hetero)arenes and Alkenes with Photoredox-Active Fluorosulfamoyl Radical Reagents

Sulfur(VI) fluoride exchange (SuFEx) is a second-generation click chemistry reaction that relies on the unique reactivities of S-VI-F bonds. The development of efficient methods for incorporating a S(VI)-F motif into molecules is of great significance. Sulfamoyl fluorides ((RRNSO2F)-R-1-N-2), serving as versatile SuFExable hubs, are typically synthesized by using "+SO2F" reagents to establish N-SO2F bonds. In this study, we report the development of N-fluorosulfamoyl pyridium salts (NFSAPs) as radical fluorosulfonamidation reagents that are readily accessible and bench-stable. By employing NFSAPs as essential fluorosulfamoyl radical (center dot NSO2F) precursors, the direct installation of the NSO2F group onto (hetero)arenes and alkenes is achieved through distinct C-N bond formation reactions. This platform facilitates the collective synthesis of highly functionalized N-aryl, N-alkyl, and N-alkenyl sulfamoyl fluorides ((RRNSO2F)-R-1-N-2) under mild photocatalytic conditions and has been applied in the late-stage functionalization of pharmaceuticals and peptides.