Catalysed esterifications in room temperature ionic liquids with acidic counteranion as recyclable reaction media

Esterification reactions of acetic acid, methoxyacetic acid and methylmalonic acid with neo-pentanol, hexanol, heptanol and decanol have been investigated in three ionic liquids with hydrogen sulphate, dihydrogen phosphate as counteranions and also two ionic liquids modified with HPF 6 as catalyst. The nature of both the counteranion and cation influence the behavior of the catalyst. Good yields and high selectivities were obtained and all the produced esters could be easily recovered due to their immiscibility with the ionic liquid as green reaction medium. © 2002 Elsevier Science B.V. All rights reserved.