Deoxyfluorination with CuF2 : Enabled by Using a Lewis Base Activating Group.

Deoxyfluorination is a primary method for the formation of C-F bonds. Bespoke reagents are commonly used because of issues associated with the low reactivity of metal fluorides. Reported here is the development of a simple strategy for deoxyfluorination, using first-row transition-metal fluorides, and it overcomes these limitations. Using CuF2 as an exemplar, activation of an O-alkylisourea adduct, formed in situ, allows effective nucleophilic fluoride transfer to a range of primary and secondary alcohols. Spectroscopic investigations have been used to probe the origin of the enhanced reactivity of CuF2 . The utility of the process in enabling 18 F-radiolabeling is also presented.