Water-mediated radical C-H tosylation of alkenes with tosyl cyanide.

The water-mediated tosylation of alkenes with tosyl cyanide was discovered. Experimental investigations revealed that the reaction was initiated by the formation of sulfinyl sulfone in the presence of water. The sulfinyl sulfone species decomposed to a sulfonyl radical and a sulfinyl radical through homolytic fission. The vinyl sulfone was afforded sequential addition of the alkene to the sulfonyl radical and the sulfinyl radical, followed by β-elimination of a sulfinyl moiety.