Recent advances in photo-induced synthesis of polycyclic quinazolinones from unactivated alkene-tethered quinazolinones

In recent years, polycyclic quinazolinone derivatives have attracted considerable attention from the synthetic organic chemistry community owing to their diverse pharmacological and biological properties. This review comprehensively summarizes recent progress (2021-2025) in photoinduced synthesis of polycyclic quinazolinones <i>via</i> radical cascade cyclization or intramolecular hydroarylation of unactivated alkene-tethered quinazolinone precursors. These methods are systematically categorized into four distinct classes based on the photocatalytic system employed: metal-based photocatalysts, organic photocatalysts, semiconductor photocatalysts, and photocatalyst-free conditions. Mechanistic insights and substrate scope are discussed in detail to highlight the synthetic versatility and limitations of each approach. Furthermore, future directions are outlined, including the development of recyclable photocatalytic systems, substrate engineering, and the use of environmentally benign solvents. We hope this review will serve as a comprehensive and practical resource for researchers engaged in the synthesis of quinazolinone-based heterocycles and related photochemical transformations.