Selective oxidation of alcohols with hydrogen peroxide catalyzed by tungstate ions (WO4=) supported on periodic mesoporous organosilica with imidazolium frameworks (PMO-IL)

Tungstate ions supported on the periodic mesoporous organosilica with ionic liquid frameworks (WO4=@PMO-IL) were found to be a recoverable catalyst system for the highly selective oxidation of various primary or secondary alcohols to the corresponding aldehydes or ketones by 30% H2O2 as green oxidant under neutral aqueous reaction conditions. The catalyst can be also recovered and efficiently reused in seven subsequent reaction cycles without any remarkable decreasing in the catalyst activity and selectivity. Moreover, N-2 sorption analysis, transmission electron microscopy (TEM) images, and thermal gravimetric analysis (TGA) showed that the structure regularity and functional groups loaded of the catalyst were not affected during the reaction process. (C) 2014 Elsevier Ltd. All rights reserved.