Modular three-component radical fluoroalkyl-sulfuration of unactivated alkenes

Abstract

The accompanied forge of C(sp³)–S and C(sp³)–C(sp³) bonds across alkene frameworks serves as a potent strategy to construct biologically important compounds. Here, we report a metal-free, photochemically mediated fluoroalkyl-mono/disulfuration of unactivated alkenes with high efficiency and high selectivity. A wide range of terminal and internal alkenes are good coupling partners, affording the expected products in moderate to good yields (>90 examples). The exceedingly mild reaction conditions, exceptional functional group tolerance, broad substrate scope, and the potential for late-stage modifications of pharmaceutical molecules highlight the utility of this method in the preparation of privileged motifs from readily available disulfides, tetrasulfides, and diselenides. Mechanistic studies suggest that a secondary alkyl radical intermediate undergoes efficient homolytic substitution with disulfides, facilitating the modular synthesis of a diverse array of unsymmetrical thioethers.