Journal article Open Access
Sandhya Rani Gogoi; Kabirun Ahmed; Gangutri Saikia; Nashreen S. Islam
Department of Chemical Sciences, Tezpur University, Napaam, Tezpur-784 028, Assam, India
Manuscript received 01 July 2018, accepted 18 July 2018
The activity of a pair of peroxoniobium(V) species immobilized on water soluble non-crosslinked polymers (WSP) formulated as, [Nb(O2)3(sulfonate)2]-PSS [PSS = poly(sodium styrene sulfonate)] (catalyst 1) and [Nb2(O2)6(carboxylate)2]-PA [PA = poly(sodium acrylate)] (catalyst 2) as efficient and recyclable catalysts for selective sulfoxidation of a variety of organic thioethers with 30% H2O2 in water, is described. A new polymer anchored macrocomplex (catalyst 1) has been synthesized from the reaction of sodium tetraperoxoniobate (NaNb) with 30% H2O2 and the macromolecular ligand poly(sodium styrene sulfonate) in an aqueous medium. The catalyst has been comprehensively characterized by spectral and other physicochemical techniques. Apart from being high-yielding and operationally simple, the additional important features which enhance the sustainability of the high yielding water-based oxidation protocol include chemoselectivity of the oxidation for sulfides and easy recyclability of the catalyst with consistent activity and selectivity for several cycles of oxidation.