Elucidation of a Parasitic Proton-Coupled Electron Transfer in a Photocatalytic Benzylic C–H Sulfonamidation

• DOI: 10.1021/acs.orglett.5c01637
• Publication Date: 2025-06-03T07:22:27Z
• Authors: Nicholas A. Fitzp...; Anna M. Howarth; Grzegorz J. Skrzypek; Jisun Lee; Hatice G. Yayla; Patricia Z. Musac...

Strategies for C-H amination with sulfonamides have been dominated by stoichiometric strategies or Rh/Cu catalysis using strong oxidants, elevated temperatures, excess equivalents of partner. We developed a photocatalytic bench-stable N-methoxypyridinium salt that is amenable to late-stage functionalization efforts. discovered competitive proton-coupled electron transfer pathway between sulfonamide and pyridine byproduct inhibits the reaction. Catalysis was re-established introduction ZnBr2.