Photocatalytic Hydrodisulfuration of Alkenes Using N-Perthiophthalimides as Perthiyl Radical Sources

The preparation of unsymmetrical disulfides remains a longstanding challenge in synthetic methodology. Harpp reagents (N-perthiophthalimides) have recently been recognized as effective radical-based platforms for disulfide unit transfer. Herein, we present a photocatalytic hydrodisulfuration of alkenes, utilizing these reagents as direct precursors to perthiyl radicals. Mechanistic studies indicate that this approach probably proceeds through the direct addition of a perthiyl radical to the alkene, followed by hydrogen atom transfer to furnish the corresponding unsymmetrical disulfide. This protocol provides straightforward access to structurally diverse, highly functionalized unsymmetrical disulfides from readily available olefins, offering a valuable entry into disulfide scaffolds for pharmaceutical and synthetic applications.