Acid-catalyzed oxidation of alkyl- and benzyl-substituted β-diketones by hydrogen peroxide at 79-120 ˚C in a mixture of an alcohol and a strong acid (sulfuric acid, tetrafluoroboric acid, or perchloric acid) gave the corresponding esters through the formation of bridged 1,2,4,5-tetraoxanes. esters - hydrogen peroxide - oxidations - tetraoxanes - ketones