Copper-Catalyzed Intramolecular C-C Bond Cleavage To Construct 2-Substituted Quinazolinones

An efficient method for a copper‐catalyzed intramolecular C–C bond cleavage to construct 2‐substituted quinazolinones has been developed. The C–C bond at the 2‐position of 2,2‐disubstituted‐1,2,3,4‐tetrahydroquinazolinone was selectively cleaved by a Cu/air catalytic system. The trend for the cleavage was dependent on the leaving group in the order of: alkyl > methyl > phenyl > substituted aryl. The process described herein provides an explanation for the mechanism of the reaction between substituted 2‐halobenzamides and α‐substituted arylmethanamines to construct 2‐substituted quinazolinones, which were previously reported and limited to the construction of 2‐arylquinazolinones. The C–C bond at the 2‐position of 2,2‐disubstituted‐1,2,3,4‐tetrahydroquinazolinones was selectively cleaved by a Cu/air catalytic system to construct 2‐substituted quinazolinones. The trend for the cleavage of the C–C bond was dependent on the leaving group in the order of: alkyl > methyl > phenyl > substituted aryl.