Monocarboxylation and Intramolecular Coupling of Butenylated Arenes via Palladium-Catalyzed C–H Activation Process

A novel and practical reaction for the direct intramolecular oxidative coupling of butenylated arenes is reported. With the catalysis of Pd­(OAc)<sub>2</sub>, reactions of various butenylated arenes and carboxylic acids with Selectfluor reagent in CH<sub>3</sub>CN solution afforded the corresponding monocarboxylation/cyclization products in good yields under mild conditions. This research demonstrated an economic method with the synthesis of 2-tetralyl carboxylic esters, a valuable class of bioactive compounds.