Efficient oxidation of sulfides catalyzed by a temperature-responsive phase transfer catalyst [(C18H37)2(CH3)2N]7 PW11O39 with hydrogen peroxide

A temperature-responsive phase transfer catalyst [(C18H37)2(CH3)2N]7PW11O39, could act as an efficient catalyst for selective oxidation of sulfides with 30% aqueous H2O2. Various kinds of sulfides were successfully oxidized to their corresponding sulfones with over 96% yields in a relatively short time and mild conditions. During reaction at 333 K, the catalyst dissolved completely and the oxidation was conducted homogeneously. Before and after reaction, the catalyst was insoluble with cooling, so it is easily recovered and reused. The catalyst was characterized by elemental analysis, FT-IR and 31P NMR.

Graphical abstractA temperature-responsive phase transfer catalyst [(C18H37)2(CH3)2N]7PW11O39 was developed and showed good activity for oxidation of sulfides to their corresponding sulfones. The catalyst acts as homogeneous during oxidation reaction at 333 K, while at room temperature it's not soluble and easily recycled.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A polyoxometalate-based temperature-responsive phase transfer catalyst was prepared. ► It efficiently catalyzed oxidation of various sulfides with H2O2 and was recyclable. ► High yields of sulfones (over 96%) were obtained in a short time and mild conditions. ► This system has both the advantage of homogeneous and heterogeneous catalysis.