Photoredox-Catalyzed Radical Cascade Cyclization of <i>N</i> -Cyanamide Alkenes with <i>N</i> -Aminopyridinium Salts: Modular Synthesis of Polycyclic Quinazolinones

2025/11/04 by Zhiwei Xu, Yuting Leng, Mengda Song +2
Chemistry · #Radical Photochemical Reactions #Catalytic C–H Functionalization Methods #Quinazolinone synthesis and applications

paper · doi:10.1021/acs.joc.5c02191

Abstract

High Resolution Image Download MS PowerPoint Slide A photoredox-catalyzed strategy enables the dual N-centered radical cascade cyclization of N -cyanamide olefins with N -sulfon/benzoylaminopyridinium salts, efficiently constructing 48 amide-decorated 2,3-fused polycyclic quinazolinones in yields of up to 86%. This metal- and base-free protocol exhibits mild reaction conditions. Moreover, they are compatible with a variety of functional groups and can accommodate a range of substrate structures. Notably, the method’s practical utility is highlighted by successful gram-scale implementation and facile downstream derivatization.

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