Abstract: The synthesis and characterization of the basic ionic liquid, 1-butyl-3-methylimidazolium imidazolide ([Bmim]Im), were reported intensively. [Bmim]Im has strong basicity and relatively good thermal stability, and it was used as a novel catalyst for the Knoevenagel reactions in aqueous media. [Bmim]Im acted as both a base catalyst and a phase transfer catalyst in the Knoevenagel reaction. In addition, [Bmim]Im together with aqueous media had good recycle ability. Aqueous media, low catalyst concentration, simple separation workup, ambient temperature, and high yield are the characteristic features of the present catalytic protocol.

Key words: imidazolide, basic, ionic liquid, aqueous media, Knoevenagel reaction