Rapid Synthesis of 3-Methyleneisoindolin-1-ones via Metal-Free Tandem Reactions of Ester-Functionalized Aziridines.

We have disclosed a novel metal-free tandem cyclization reaction for the synthesis of 3-methyleneisoindolin-1-ones starting from ester-functionalized aziridines. This strategy can be effectively promoted by DBU and carboxylic acids. Mechanistically, it involves sequential ring opening of aziridines with carboxylic acids, lactamization, and elimination of carboxylic acids.