Multi-wall Carbon Nanotubes Supported Molybdenum Acetylacetonate: Efficient and Highly Reusable Catalysts for Oxidation of Sulfides with Tert-butyl Hydroperoxide

Abstract

In the present work, highly efficient oxidation of sulfides catalyzed by MoO2(acac)2 supported on multi-wall carbon nanotubes, MWCNTs, modified with 1,2-diaminobenzene (DAB) and 2-aminophenol (AP), at room temperature are reported. The effects of various parameters such as reaction time, solvent, catalyst amount, oxidant, etc, were studied. These heterogenized catalysts showed high activity in the oxidation of a variety of linear, cyclic and aromatic sulfides with tert-butyl hydroperoxide (TBHP) in 1,2-dichloroethane as solvent under mild conditions. In these systems sulfides have been selectively oxidized to the corresponding sulfoxides and sulfones with short reaction times and high yields. In the case of aromatic sulfides, sulfoxide was produced as major product and in the case of linear sulfides only sulfoxide was produced. The [MoO2(acac)@amines-MWCNT] catalysts are stable under the reaction conditions and While, the homogeneous MoO2(acac)2 cannot recovered even one time, the MWCNT supported catalysts can be filtered and reused several times without significant loss of their activity.