Catalytic Defluoroalkylation of Trifluoromethylaromatics with Unactivated Alkenes
1Department of Chemistry and Winship Cancer Institute, Emory University , Atlanta, Georgia 30322, United States.
Abstract:
We describe a new catalytic approach to selective functionalization of the strong C-F bonds in trifluoromethylaromatic (Ar-CF3) systems. In this approach, single electron reduction of Ar-CF3 substrates (using a photoredox catalyst) results in difluorobenzylic radical formation through a C-F cleavage mechanism. These radicals undergo efficient intermolecular coupling with simple alkenes in a defluoroalkylation process where radical termination is accomplished by a polarity reversal catalyst. This mild catalytic protocol engages a wide range of substrates to give medicinally relevant fluorinated substructures with complete regiocontrol.
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