Iridium-Catalyzed Enantioselective Fluorination of Racemic, Secondary Allylic Trichloroacetimidates
Qi Zhang1, David P Stockdale1, Jason C Mixdorf1
1Department of Chemistry, University of Iowa , Iowa City, Iowa 52242, United States.
Abstract:
The Ir-catalyzed enantioselective fluorination of racemic, branched allylic trichloroacetimidates with Et3N·3HF is a mild and efficient route for selective incorporation of fluoride ion into allylic systems. We herein describe the asymmetric fluorination of racemic, secondary allylic electrophiles with Et3N·3HF using a chiral-diene-ligated Ir complex. The methodology enables the formation of acyclic fluorine-containing compounds in good yields with excellent levels of asymmetric induction and overcomes the limitations previously associated with the enantioselective construction of secondary allylic fluorides bearing α-linear substituents.
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