B(C 6 F 5 ) 3 -Catalyzed Michael Reactions: Aromatic C-H as Nucleophiles.

The Michael reaction is a widely used reaction for the C-C coupling of electron-poor olefins and C(sp3 )-H pronucleophiles. Herein we report the Michael reaction between alkenes and aromatic as well as heteroaromatic compounds as aromatic C(sp2 )-H nucleophiles under mild conditions. The reaction is catalyzed by readily available Lewis acidic B(C6 F5 )3 and proceeds with high regioselectivity for a wide substrate scope.