A metal-free oxidative tandem coupling of activated alkenes with carbonyl C(sp²)–H bonds and aryl C(sp²)–H bonds using TBHP is established for the synthesis of 3-(2-oxoethyl)indolin-2-ones. This method allows 1,2-difunctionalization of the C–C double bond in N-arylacrylamides by simultaneous formation of two C(sp²)–C(sp³) bonds.

DTBP (di-tert-butyl peroxide) is utilized to mediate oxidative 1,2-difunctionalization of activated alkenes with an aryl C(sp²)–H bond and a benzylic C(sp³)–H bond for the synthesis of functionalized oxindoles. This reaction is a new organomediated strategy for alkene difunctionalization facilitated by Lewis acids.