Metal-free electrochemical synthesis of sulfinamides via alkyl radical addition to sulfinylamines

Sulfinamides are important sulfur-containing motifs with broad applications in pharmaceuticals, agrochemicals, and materials. Traditional alkyl sulfinamide synthesis often requires prefunctionalized organometallic reagents or stoichiometric oxidants, limiting functional group tolerance. Herein, we report a metal-free electrochemical strategy for synthesizing alkyl sulfinamides via coupling alkyl iodides or NHPI esters with sulfinylamines under mild conditions. This protocol employs direct anodic or cathodic activation of alkyl halides or redox-active esters to generate alkyl radicals, which undergo S=N bond addition with sulfinylamines to yield sulfinamide products. The method features a broad substrate scope, including primary, secondary, and tertiary alkyl groups, and enables late-stage functionalization of complex natural products and drug molecules with excellent functional group compatibility. Mechanistic studies suggest a radical pathway without external metal catalysts or harsh reagents. This electrochemical approach provides a practical and sustainable route to diverse sulfinamide derivatives, offering valuable synthetic tools for medicinal chemistry applications. We developed a metal-free electrochemical method to access diverse alkyl sulfinamides via radical coupling of alkyl iodides or NHPI esters with sulfinylamines under mild conditions, enabling late-stage functionalization of complex molecules with broad functional group tolerance.