One-Pot Synthesis of 4-Quinolone via Iron-Catalyzed Oxidative Coupling of Alcohol and Methyl Arene.

Herein, we describe the iron(III)-catalyzed oxidative coupling of alcohol/methyl arene with 2-amino phenyl ketone to synthesize 4-quinolone. Alcohols and methyl arenes are oxidized to the aldehyde in the presence of an iron catalyst and di--butyl peroxide, followed by a tandem process, condensation with amine/Mannich-type cyclization/oxidation, to complete the 4-quinolone ring. This method tolerates various kinds of functional groups and provides a direct approach to the synthesis of 4-quinolones from less functionalized substrates.