Silver-Assisted Difunctionalization of Terminal Alkynes: Highly Regio- and Stereoselective Synthesis of Bromofluoroalkenes

The difunctionalization of terminal alkynes was achieved with silver fluoride (AgF) and N-bromosuccinimide (NBS) as halogen sources. The presence of the halide moiety greatly enhances the reactivity of the vinyl fluoride compounds that can probably can be transformed into various products that are difficult or even impossible to obtain via direct fluorination. Meanwhile, the monofluoro <.> alkenes were facilely synthesized via a highly chemo- and regioselective fluorination of electron-deficient C C triple bonds using AgF as fluorinating reagent in good yields.