Esterification of carboxylate-based ionic liquids with alkyl halides

A facile reaction of 1-ethyl-3-methylimidazolium acetate ([EMIm]Ac) with dichloromethane at room temperature was observed with esters among the products. This esterification can be exploited for mild solvent-free esterification with a range of other carboxylate-based ionic liquids and alkyl halides.