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

From the Musacchio Lab (Buffalo) and #PfizerChemistry is a new #OLasap with #PhotoChem C-H amination with sulfonamides - great scope. LA addition was key to eliminate competing pathway

Synthesis of 4-Amino-5-nitro-7H-pyrazolo[3,4-d][1,2,3]triazine-2-oxide and Its Heat-Resistant Derivatives 4-Amino-5-nitro-7H-pyrazolo[3,4-d][1,2,3]triazine-2-oxide (PTO) is synthesized via one step in this study. Subsequently, 4,7-diamino-5-nitro-pyrazolo[3,4-d][1,2,3]triazine-2-oxide (APTO), 4-oxo-5-nitr...

Some new heterocycles I will NOT be incorporating into any new drug designs
(Well, ADCs use “warheads” but that’s not my space) #ChemSky
#OLasap

Lewis Acid-Catalyzed Sulfur Fluoride Exchange A new method uses metal Lewis acids as catalysts to convert sulfonyl fluorides, fluorosulfates, and sulfamoyl fluorides with silyl amines into S–N bond-containing compounds via sulfur fluoride exchang...

Another fantastic paper from @theballlab featuring Nicholas Ball and his amazing band of @PomonaCollege undergraduates – optimization of Lewis acid-catalyzed SuFEx reactions of R-SO2F with TMS-amines using now out in @JOC_OL #OLasap #ChemSky
pubs.acs.org/doi/10.1021/...