Chemo‐ and Regioselective Construction of Functionalized Isocoumarin, Flavone, and Isoquinolinedione via a One‐pot Reaction of o‐Quinol Acetate and Soft Nucleophiles

A one‐pot strategy for the synthesis of substituted isocoumarin, flavone, and isoquinolinedione derivatives through a switchable C‐arylation/lactonization or SNAr reaction from a wide range of soft nucleophiles and o‐quinol acetates has been developed. This base‐mediated protocol proceeds under transition‐metal‐free conditions and selectively affords various heteroarenes in 13–98% yields from readily prepared or commercially available 1,3‐dicarbonyl and α‐EWG‐substituted carbonyl compounds. The synthetic utility is further demonstrated in the synthesis of potential anti‐HIV and anti‐coronavirus derivatives and COX‐2 inhibitors. In addition, detailed experimental and computational studies are performed to provide an intensive understanding and strong support of the reaction mechanism.