α-Fluorination of Sulfides with N-Fluoropyridinium Triflates

Article abstract of DOI:10.1246/bcsj.59.3625

The reaction of sulfides possessing α-hydrogen with various N-fuoropyridinium salts was examined.While the fluorinating power increased in the order of N-fluoro-2,4,6-trimethylpyridinium triflate 12, and 3 no longer produced the α-fluoro sulfide.Triflate 1 was more reactive than the corresponding tetrafluoroborate 4.Thus, it was shown that 1 satisfactorily fluorinated various kinds of sulfides under very mild conditions, giving α-fluoro sulfides.A two-step mechanism, oxidative fluorination of sulfur and Pummerer-type rearrangement, was proposed for the fluorination.The corresponding α-fluoro sulfoxide or sulfones were easily prepared from the sulfides by successive fluorination-oxidation procedure.