Aerobic oxidation of isopropylaromatic hydrocarbons to hydroperoxides catalyzed by N-hydroxyphthalimide

The oxidations of cumene, 4-isopropylbiphenyl, 1-methoxy-4-(1-methylethyl)benzene, 2-isopropylnaphthalene, 2-methoxy-6-(1-methylethyl)naphthalene, 2,6-diisopropylnaphthalene and 4,4′-diisopropylbiphenyl to the corresponding hydroperoxides with oxygen, at 60 °C, in the presence of N-hydroxyphthalimide (NHPI) and AIBN have been performed. Process inhibition was observed at temperatures above 60 °C resulting in lower conversion. A favorable effect of electron-donating substituents (methoxy, phenyl) on the reaction rate were described. NHPI was separated from the cumene oxidation product and recycled 5 times. It has been demonstrated that oxygen can be replaced by air.