Electrochemical C–H Sulfonation of Aminoquinones with Sulfonyl Hydrazides

We report an efficient, metal-free electrochemical synthesis of sulfonylated aminoquinones via electrooxidative denitrogenation of sulfonyl hydrazides. Anodic denitrogenation generates sulfonyl radicals that undergo chemo- and regioselective addition to aminoquinones, affording diverse products in 52–90% isolated yields with broad functional group tolerance. Mechanistic studies involving cyclic voltammetry and radical trapping support a sulfonyl radical addition pathway. The synthetic utility is demonstrated by converting ortho -fluorophenylsulfonylated products into tetracyclic quinones via base-promoted nucleophilic aromatic substitution.