6533b7dbfe1ef96bd1270ceb

RESEARCH PRODUCT

Thiazolium-based catalysts for the etherification reaction of benzylic alcohols under solvent-free condition

Carmela AprileMichelangelo GruttadauriaMireia Buaki-sogoFrançois QuertinmontHazi Ahmad BeejapurLucia Anna BivonaLucia Anna BivonaFrancesco Giacalone

subject

Solvent freecatalysisChemistryHomogeneous catalysissupported catalystGeneral ChemistrycatalysiSettore CHIM/06 - Chimica OrganicaorganocatalysiHeterogeneous catalysisCatalysisheterogeneous catalysisOrganocatalysissynthetic methodsOrganic chemistryheterogeneous catalysiorganocatalysisSynergistic catalysissupported catalysts

description

Thiazolium and imidazolium hybrid materials were prepared by radical reactions between a mercaptopropyl-modified SBA-15 mesoporous silica and bis-vinylthiazolium or bis-vinylimidazolium dibromide salts. These hybrid materials were characterized by several techniques and were employed in the etherification reaction of 1-phenylethanol. Solvent-free conditions at 160C under different gas phases (oxygen, air, nitrogen and argon) were used. The thiazolium-based material displayed excellent performances. Further studies were carried out using unsupported thiazolium salts, with or without a methyl group at the C-2 position of the thiazolium moiety. These studies allowed us to propose a reaction mechanism. The supported thiazolium-based material was successfully used in the etherification reaction of two other benzylic alcohols and also in seven consecutive cycles. This work represents the first use of thiazolium-based compounds as catalysts for the etherification reaction of alcohols.

10.1002/adsc.201400733http://hdl.handle.net/10447/122392