Vanadium-catalyzed, microwave-assisted oxidations with H<sub>2</sub>O<sub>2</sub> in ionic liquids

Conte, Valeria; Fabbianesi, Francesca; Floris, Barbara; Galloni, Pierluca; Sordi, Daniela; Arends, Isabel W. C. E.; Bonchio, Marcella; Rehder, Dieter; Bogdal, Dariusz

doi:10.1351/PAC-CON-08-09-19

Pure Appl. Chem., 2009, Vol. 81, No. 7, pp. 1265-1277

http://dx.doi.org/10.1351/PAC-CON-08-09-19

Published online 2009-06-29

Vanadium-catalyzed, microwave-assisted oxidations with H₂O₂ in ionic liquids

Valeria Conte¹*, Francesca Fabbianesi¹, Barbara Floris¹, Pierluca Galloni¹, Daniela Sordi¹, Isabel W. C. E. Arends², Marcella Bonchio³, Dieter Rehder⁴ and Dariusz Bogdal⁵

¹ Department of Science and Chemical Technology, University of Rome Tor Vergata, via Ricerca Scientifica, 00133, Rome, Italy
² Biocatalysis and Organic Chemistry, Department of Biotechnology, Delft University of Technology, Delft, Netherlands
³ ITM-CNR and University of Padua, Department of Chemical Science, via Marzolo 1, 35131, Padua, Italy
⁴ Institute of Inorganic and Applied Chemistry, Hamburg University, Martin-Luther-King-Platz, 6 D-20146 Hamburg, Germany
⁵ Department of Chemistry and Technology, Politechnika Krakowska ul. Warszawska 24, 3-155 Krakow, Poland

Abstract: The application of vanadium(V) catalysts in selective oxidation with peroxides offers an efficient procedure that is compatible with different functional groups and leads to good yields and selectivities. However, the search for more efficient and sustainable procedures that employ H₂O₂ as oxidant remains an important topic. In the last few years, striking results have been obtained by applying microwave (MW) activation in metal-catalyzed reactions carried out in ionic liquids (ILs). In the present study, results achieved with vanadium-based catalysts in oxidations of various substrates with H₂O₂ are presented; in particular, epoxidation of alkenes and sulfoxidation of thioethers have been investigated. Notably, in the latter oxidation, a significant improvement in the rate of reaction and an increase in selectivity have been observed in the case of hydrophobic ILs in combination with MW activation.