Tungstate supported on magnetic ionic liquid-modified graphene oxide as an efficient and recyclable catalyst for the selective oxidation of sulfides

An effective and recyclable catalyst based on tungstate ion immobilization on magnetic ionic liquid modified graphene oxide (WO4@Fe3O4/GO-IL) has been synthesized in this research. The catalyst was characterized by various techniques such as Raman spectroscopy, X-ray diffraction, thermogravimetric analysis, electron microscopy transmission and scanning, and vibrating sample magnetometer. Also, for the selective oxidation of sulfides to the corresponding sulfoxides, the as-synthesized catalyst was investigated. Additionally, the WO4@Fe3O4/GO hybrid was used to study the role of ionic liquid in this transformation and, the observed yield of methyl phenyl sulfoxide was remarkably inferior. Also, by using an external magnet, the catalyst can be quickly retrieved and recycled successfully in five following reaction cycles without any significant reduction in activity and selectivity of the catalyst.