A dicationic ionic liquid-modified phosphotungstate hybrid catalyst for the heterogeneous oxidation of alcohols with H2O2

Article abstract of DOI:10.1007/s11426-012-4722-7

An ionic hybrid catalyst 1,1'-(butane-1,4-diyl)-bis(3-methylimidazolium) phosphotungstate (abbreviated [Dmim]1.5PW) has been prepared by anion-exchange of the divalent ionic liquid (IL) 1,1'-(butane-1,4-diyl)-bis(3- methylimidazolium) di(bromide) with the Keggin phosphotungstic acid H ₃PW₁₂O₄₀, and characterized by IR, ¹H NMR, ¹³C NMR, ESI-MS, TG, SEM, XRD, BET surface area measurements, elemental analysis, and melting point. The hybrid material was evaluated as a catalyst for the oxidation of alcohols with aqueous hydrogen peroxide under various conditions. The catalytic performance of [Dmim] _1.5PW was also compared with related catalysts bearing other cations or anions. The new hybrid [Dmim]_1.5PW proved to be an efficient liquid-solid heterogeneous catalyst for H₂O₂-based oxidation of alcohols, with the advantages of high conversion and selectivity, easy recovery, and quite good reusability. Science China Press and Springer-Verlag Berlin Heidelberg 2012.