Polyvinylpolypyrrolidone-Supported Hydrogen Peroxide (PVP-H2O2), Silica Sulfuric Acid and Catalytic Amounts of Ammonium Bromide as Green, Mild and Metal-Free Oxidizing Media for the Efficient Oxidation of Alcohols and Sulfides

Polyvinylpolypyrrolidone-supported hydrogen peroxide (PVP-H2O2), silica sulfuric acid (SiO2OSO3H) and catalytic amounts of ammonium bromide (NH4Br) are introduced as green media for the in situ generation of bromoniume ion (Br+), which was applied for the selective oxidation of sulfides and alcohols into sulfoxides and carbonyl compounds, respectively. The oxidation reactions were carried out heterogeneously in acetonitrile, as solvent, at room temperature (oxidation of sulfides) and/or 60 °C (oxidation of alcohols).