Using the Thiyl Radical for Aliphatic Hydrogen Atom Transfer: Thiolation of Unactivated C–H Bonds

Metal- and catalyst-free thiyl radical-mediated activation of alkanes is described. Tetrafluoropyridinyl disulfide is used to perform thiolation of the C-H bonds under irradiation with 400 nm light emitting diodes. The key C-H activation step is believed to proceed via hydrogen atom abstraction effected by the fluorinated thiyl radical. Secondary, tertiary and heteroatom-substituted C-H bonds can be involved into the thiolation reaction. The resulting sulfides have wide potential as photoredox-active radical precursors in reactions with alkenes and heteroarenes.