Pd-Catalyzed C-H Activation Route to 3-(Methylenyl)indolinones

Significance

Starting from readily available anilides and iodoarenes, a Pd-catalyzed sequential intramolecular carbopalladation/C-H activation process has been developed for the synthesis of 3-(diarylmethylenyl)indolinones. The reaction proceeds in good to excellent yields and tolerates variation in R¹, R² and Ar substituents but lacks provision of scope with respect to R³ substitution. Mechanistic studies indicate that the C-H activation step likely proceeds through a proton-abstraction mechanism.