Iodine-promoted sequential C(sp3)–H oxidation and cyclization of aryl methyl ketones with 2-(2-aminophenyl)quinazolin-4(3H)-ones

Abstract

An I₂-promoted, metal-free protocol has been developed for the one-pot synthesis of 6-aroyl-5,6-dihydro-8H-quinazolino[4,3-b]quinazolin-8-ones from readily accessible substrates. This reaction involves the in situ sp³ C–H oxidation of aryl methyl ketones to phenylglyoxal, followed by imine formation and intramolecular nucleophilic addition, resulting in the formation of two new C–N bonds. Furthermore, the method is applicable to a wide range of aryl methyl ketones, including heterocycles and drug-derived substrates, yielding the desired products with yields ranging from 62% to 93%. Additionally, the practical utility of this approach was demonstrated through gram-scale synthesis.