Photocatalyst-free synthesis of quinazolinones from <i>o</i> -aminobenzamides and rongalite under visible light

A photocatalyst-free method has been developed for the synthesis of quinazolinones from <i>o</i>-aminobenzamides and rongalite as a C₁ synthon under visible light for the first time. This transformation proceeds using atmospheric oxygen as the oxidant, involving the <i>in situ</i> generation of a superoxide radical anion (O₂˙^-), as supported by EPR analysis. Additionally, the formation of H₂O₂ was confirmed by UV-Vis spectrophotometric analysis. Key features of this method include broad functional group tolerance, moderate to good yields, gram-scale applicability, and a proof-of-concept demonstration of <i>N</i>-formylation using <i>p</i>-anisidine.