Synthesis of Quinazolines via an Iron-Catalyzed Oxidative Amination of N-H Ketimines

An efficient synthesis of quinazolines based on an iron-catalyzed C(sp(3))-H oxidation and intramolecular C-N bond formation using tent-BuOOH as the terminal oxidant is described. The reaction of readily available 2-alkylamino benzonitriles with various organometallic reagents led to 2-alkylamino N-H ketimine species. The FeCl2-catalyzed C(sp(3))-H oxidation of the alkyl group employing tert-BuOOH followed by intramolecular C-N bond formation and aromatization afforded a wide variety of 2,4-disubstituted quinazolines in good to excellent yields.