Construction of 3‐Substituted Phthalides via Lewis Acid‐Catalyzed Intramolecular Ring Opening of Aziridines with Esters

Abstract A new strategy for the synthesis of 3‐substituted phthalides has been developed via a Lewis acid‐catalyzed intramolecular ring opening of aziridines with esters. Broad substrate scope, good yields and mild conditions made the cyclization reaction very suitable for the rapid construction of libraries of 3‐substituted phthalide compounds.