Copper-Catalyzed Diarylation of Activated Alkenes with Diaryliodonium Salts

Cu(OTf)₂-catalyzed diarylation of activated alkenes by using diaryliodonium(III) salts has been developed. With this method, arylated oxindoles can be easily accessed in good yields. Insights into the mechanism of copper-catalyzed arylations are discussed, and the findings are expected to help increase the level of understanding of catalytic arylations with diaryliodonium salts.