Base-Mediated Allylic Defluorinative Functionalizations of β-CF 2 H-1,3-enynes Enables the Construction of Terminal Monofluoroenynes.

The base-mediated allylic defluorinative functionalization of β-CF 2 H-1,3-enynes with nucleophiles is described, affording terminal monofluoroalkenes bearing an alkynyl group in synthetically useful yields and Z / E selectivities. Importantly, the resultant Z / E mixture could be separated by flash chromatography in all cases; thus, stereoisomerically pure monofluoroenynes were obtained. Postsynthetic modifications of the synthesized monofluoroenynes were also accomplished to access diverse molecular structures. Computational studies disclosed the origin of the diastereoselectivity.