Catalytic oxidation of aniline by aqueous hydrogen peroxide in the presence of some heteropolyoxometalates

Abstract

Aniline was selectively converted into the corresponding nitrosobenzene and nitrobenzene by oxidation with 30% aqueous hydrogen peroxide. The reaction was catalyzed by various heteropolyoxometalates, at room temperature, in dichloromethane under two-phase conditions. Findings show that H 3PW12O40 is the best catalyst in the oxidation of aniline. Na3PW9Mo3O40 and K 4SiW9Mo2O39 also displayed high reactivity in the oxygenation system. Phase transfer agents and temperature increase also contribute to the efficiency of the oxidation. ©2005 Sociedade Brasileira de Química.