Supported metal oxides and n-hydroxyphthalimide in catalysis of the oxidation of benzylic C-H bonds

Abstract

The aerobic liquid-phase oxidation of alkylarene (RH) in the presence of a binary catalytic system containing N-hydroxyphthalimide (NHPI) and supported V, Mn, and Cu oxides (TMO) was studied. The heterogeneous catalysts with single active component such as V2O5, MnOx, and CuOx and bi-components V2O5-MoO3 V2O5-WO3, and V2O5-SbOx supported onto TiO2, TiO2-SiO2, and Al2O3-SiO2 were prepared and characterized. The kinetics of the aerobic oxidation of alkylarene in the presence of a binary catalytic system NHPI and TMO was studied using molecular oxygen (under 760 mm Hg) and acetonitrile (ACN) as a solvent, with volume ratio of cumene to ACN as 1:1, and the reaction temperature was 70 °C. The major product of cumene oxidation was cumene hydroperoxide. Correlation was found between the catalytic activity of the TMO + NHPI system and the acidic properties of TMO (measured by NH3 TPD).