The dual role of ionic liquid BmimBF(4), precursor of N-heterocyclic carbene and solvent, in the oxidative esterification of aldehydes

作者：Chiarotto Isabella^*; Feroci Marta; Sotgiu Giovanni; Inesi Achille

来源：Tetrahedron, 2013, 69(37): 8088-8095.

DOI：10.1016/j.tet.2013.06.014

• Esters
• N-Heterocyclic carbene
• Aldehydes
• Umpolung
• Room temperature ionic liquid
• Oxidations

Room temperature ionic liquid BmimBF(4) (1-butyl-3-methylimidazolium tetrafluoroborate) has been utilized in the N-heterocyclic carbene-catalyzed oxidation of aldehydes to yield esters. In the presence of MnO2 as oxidant and of DBU and caesium carbonate as bases, aromatic, heteroaromatic and aliphatic esters have been isolated in good to excellent yields. The recyclability of the used ionic liquid along with the excess of inorganic reagents has been proved. The simple and cheap BmimBF4 ionic liquid played the dual role of precatalyst and solvent. This is the first time that such a reaction has been carried out with an ionic liquid as solvent.

• 出版日期2013-9-16