Iodine-Catalyzed Room-Temperature Aerobic Oxidation of C(<i>sp</i>³)–H Bonds and Its Application in the Synthesis of Quinoxaline Derivatives

An iodine-catalyzed aerobic oxidation reaction of C(<i>sp</i>³)-H bonds was established at room temperature. In this transformation, iodine acts as a Lewis acid catalyst, and the pyridine moiety in the substrate plays a crucial role. Under the optimum reaction conditions, picolyl ketone substrates were smoothly transformed into the corresponding 1,2-dicarbonyl compounds, and the subsequent introduction of 1,2-diaminobenzenes into the reaction mixture led to the formation of various quinoxaline derivatives. This synthetic process does not use transition metals and also features mild reaction conditions, operational simplicity, and gram-scale synthesis.