Tungsten-catalyzed continuous-flow oxidation of sulfides to sulfones with hydrogen peroxide

Abstract

Continuous-flow oxidation of sulfides to sulfones was achieved with hydrogen peroxide (H2O2) using a column packed with a mixture of oxodiperoxotungstate–2,2’-bipyridine and activated carbon. Sulfones were continuously produced in more than 90% yield for up to 160 h by simply passing an acetonitrile solution of sulfides and H2O2 through the catalyst column. Selective oxidation to sulfone took place under continuous-flow conditions even though the sulfide substrates contained other oxidizable functional groups, such as olefinic double bond, hydroxy group, and pyridyl and amino functional groups.