Ionic liquid mediated esterification of alcohol with acetic acid

Abstract

Highly efficient esterification of alcohols with acetic acid by using a Brønsted acidic ionic liquid, i.e., 1-methyl-2-pyrrolidonium hydrogen sulfate ([Hnmp]HSO₄), as catalyst has been realized. The turnover numbers (TON) were able to reach up to 11000 and turnover frequency (TOF) was 846. The catalytic system is suitable for the esterification of long chain aliphatic alcohols, benzyl alcohol and cyclohexanol with good yields of esters. The procedure of separating the product and catalyst is simple, and the catalyst could be reused. [Hnmp]HSO₄ had much weaker corrosiveness than H₂SO₄. The corrosive rate of H₂SO₄ was 400 times more than that of [Hnmp]HSO₄ to stainless steel.

Keywords

ionic liquid / Brønsted acid / esterification / catalyst

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Acknowledgements

This work was financially supported by the National Natural Science Foundation of China (Grant No. 20376015), Guangdong Provincial Natural Science Foundation (32491), the Foundation of Scientific and technological Planning Project of Guangzhou of China (2004J1-C0151 ).

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg