Palladium-Catalyzed Dearomatization of Benzothiophenes: Isolation and Functionalization of a Discrete Dearomatized Intermediate

Abstract

A Pd-catalyzed decarboxylative dearomatization reaction of of a heterocyclic substrate enables access to an uncommon reaction intermediate, that rearomatizes in the presence of amine bases in a net C–H functionalization sequence. The dearomatized benzo[b]thiophene intermediate bears an exocyclic alkene that can be functionalized through cycloaddition and halogenation reactions to deliver complex heterocyclic products.