Synthesis of Aminofuranquinoxalinones from a Two-Step Cascade: Photoinduced TFA-Promoted Coupling of Quinoxalin-2(1H)-ones with 3-Acetamidofuran and Hydrolysis

A protocol of C-C direct coupling of the C-2 position of 3-acetylaminofuran, derived from biomass, with quinoxalinone was reported for the first time. This study confirmed that the quinoxalinone free radical, generated by acid protonation and illumination, is used to perform C-C dehydrogenation coupling with 3-acetylaminofuran (3AF), in which oxygen participates in the reaction process. On this basis, acid-catalyzed deacetylation was used to obtain the corresponding aminofuran derivatives. Intramolecular dehydration can be realized to form an imine tetracyclic compound.