A Novel Category of Ionic Liquids Based on Diacetone Acrylamide Cation and Their Use as Esterification Catalysts

A novel category of salts based on diacetone acrylamide cation (DA⁺) and the anions such as acetate (Ac⁻), trifluoroacetate (TF⁻), tetrafluoroborate (BF⁻), hexafluorophosphate (PF⁻), sulfate (SO⁻) and chloride (Cl⁻) were synthesized by usual neutralization of acids and bases at room temperature and characterized by IR, ¹H NMR and elemental analysis (EA). The results show that these compounds possess the characteristic of ionic liquids. In addition, four of them, DABF, DACl, DASO and DAPF, were efficient catalysts for esterication of acetic acid with C₁–C₆ alcohols and octanol.