Selective Mono- and Dialkynylation of 1-Fluoro-2,2-diiodovinylarenes Using Pd-Catalyzed Decarboxylative Coupling Reactions.

Palladium-catalyzed decarboxylative coupling reactions using alkynoic acids and 1-fluoro-2,2-diiodovinylarenes provide mono- and dialkynylfluoroalkenes with high selectivity. When the reaction was conducted using DBU/DMSO, the hydrodeiodinated monoalkynylfluoroalkene product was formed, whereas performing the reaction using EtN/THF gave the dialkynylfluoroalkene product. Both reaction conditions gave high yields of the desired enyne and endiyne products bearing fluorine atoms.