Direct Hydrodefluorination of CF3-Alkenes via a Mild SN2' Process Using Rongalite as a Masked Proton Reagent
Xiang-Long Chen1, Dong-Sheng Yang1, Bo-Cheng Tang2
1Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, P. R. China.
Abstract:
A concise and efficient hydrodefluorination process was developed for the synthesis of gem-difluoroalkenes. This reaction employs rongalite as a masked proton source and does not require any additional catalysts or reductants. Notably, trifluoromethyl alkenes having both terminal and internal double bonds are compatible with this process, allowing for a wider range of substrates. The successful late-stage functionalizations of pharmaceuticals and gram-scale syntheses were used to demonstrate the viability of this method.
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