Synthesis and Reactivity of α-Cumyl Bromodifluoromethanesulfenate: Application to the Radiosynthesis of [18 F]ArylSCF3.

A highly reactive electrophilic bromodifluoromethylthiolating reagent, α-cumyl bromodifluoro-methanesulfenate 1, was prepared to allow for direct bromodifluoromethylthiolation of aryl boron reagents. This coupling reaction takes place under copper catalysis, and affords a large range of bromodifluoromethylthiolated arenes. These compounds are amenable to various transformations including halogen exchange with [18 F]KF/K222  , a process giving access to [18 F]arylSCF3 in two steps from the corresponding aryl boronic pinacol esters.