ION-RADICAL PERFLUOROALKYLATION .11. PERFLUOROALKYLATION OF THIOLS BYPERFLUOROALKYL IODIDES IN THE ABSENCE OF INITIATORS

Perfluoroalkylation of aliphatic, aromatic and heterocyclic thiols by perfluoroalkyl iodides in the presence of Et(3)N appears to occur spon taneously under daylight or the usual laboratory lighting conditions a t 20-22 degrees C and is complete in 10-15 min to 2-3 h. An exception to this rule are thiols with a low nucleophilicity. The reaction is ac companied by thiol oxidation (2%-3%) and depends directly on the tempe rature, lighting, solvent polarity and electronic properties of the pe rfluoroalkylating agents and of the thiol substituents. At the same ti me, formation of diaryl disulphides frequently occurs contrary to abov e rules. The reaction mechanism is discussed.