Iron‐Catalyzed Intramolecular Arene C(sp²)−H Amidations under Mechanochemical Conditions

Abstract

In a ball mill, FeBr3‐catalyzed intramolecular amidations lead to 3,4‐dihydro‐2(1H)‐quinolinones in good to almost quantitative yields. The reactions do not require a solvent and are easy to perform. No additional ligand is needed for the iron catalyst. Both 4‐substituted aryl and β‐substituted dioxazolones provide products with high selectivity. Mechanistically, an electrophilic spirocyclization followed by C−C migration explains the formation of rearranged products.