Selective oxidation of sulfides to sulfoxides using novel nano Bronsted dicationic ionic liquid as effective reagent under grinding conditions

In this work, 1,1'-(butane-1,4-diyL)bis(1,4-diazabicydo[2.2.2]octane-1,4-diium) bis(hydrogen sulfate) dinitrate ([C-4(DABCO-H)(2)]center dot[HSO4](2)[NO3](2)) as a novel Brhnsted dicationic ionic liquid was prepared with available starting materials, and characterized by FT-IR, H-1 NMR, C-13 NMR, TGA, DSC, SEM and FESEM techniques. This nano-sized regent was efficiently employed in selective oxidation of sulfides to sulfoxides at room temperature, under grinding and solvent-free condition. A simple method, short reaction times, high yields, green and easy work-up of the products, use of commercial cheap starting materials and excellent selectivity are attractive features of the present method. (C) 2018 Published by Elsevier B.V.