Base-Mediated Allylic Defluorinative Functionalizations of β-CF2H-1,3-enynes Enables the Construction of Terminal
Zhi-Qing He1, Shu-Jie Chen1, Guo-Shu Chen1
1School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P.R. China.
Abstract:
The base-mediated allylic defluorinative functionalization of β-CF2H-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.
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