cis-Aziridines From Terminal Alkenes via Diastereoselective Intramolecular Electrocatalytic Hydroamination.

Aziridines are valuable building blocks with broad synthetic and biological relevance, yet general strategies for accessing 2,3-disubstituted aziridines from stereochemically undefined starting materials with predictable stereochemical outcomes remain scarce. Conventional diazo- and nitrene-based aziridinations rely on hazardous precursors, tolerate limited substrate diversity, and deliver stereochemical outcomes that are largely dictated by the geometry of the starting materials. Here we report an electrocatalytic cobalt-catalyzed hydroamination that converts readily available allylic sulfonamides into cis-2,3-disubstituted aziridines. Mechanistic experiments, together with density functional theory (DFT) analysis, support a model in which diastereoselectivity is established during solvent-caged radical recombination rather than by the geometry of the starting alkene. The resulting cis-aziridines also undergo predictable and synthetically useful derivatizations, highlighting their value as functional intermediates. This operationally simple and scalable protocol provides direct access to stereochemically enriched cis-aziridines without recourse to diazo or nitrene chemistry.