Photo-Induced Electrophilic Aromatic Substitution of Ferric Acyl Nitrene

A photo-induced intramolecular electron-aromatic-substitution (SEAr) of N-acyloxybenzozmide under 20 mol% FeCl3 at 1, 4-dioxane is reported for the synthesis of biologically interesting benzoxazin-3(4H)-ones. In the reaction, it is believed that blue LED facilitates the reaction, like reaction temperature serving as source of energy. The reaction SEAr pathway was ascribed to the electron effect in aryl ring of substrates. The reaction was also applicable for the synthesis of useful scaffolds possessing a quinolin-2-one core, such as anticancer reagent 4, brexipiprazole and cilostamide analogues.