Electrophotocatalytic C-H Functionalization of Ethers with High Regioselectivity
He Huang1, Zack M Strater2, Tristan H Lambert1,2
1Department of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14853 , United States.
Abstract:
The highly regioselective electrophotocatalytic C-H functionalization of ethers is described. These reactions are catalyzed by a trisaminocyclopropenium (TAC) ion at mild electrochemical potential with visible light irradiation. Ethers undergo oxidant-free coupling with isoquinolines, alkenes, alkynes, pyrazoles, and purines with typically high regioselectivity for the less-hindered α-position. The reaction is proposed to operate via hydrogen atom transfer (HAT) from the substrate to the photoexcited TAC radical dication, thus demonstrating a new reactivity mode for this electrophotocatalyst.
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