Abstract: As a new novel media for chemical reaction, room temperature ionic liquids(RTILs) are recognized and accepted, because of many novel properties which are shown on RTILs. Research on the multivalent ionic liquids has been less reported, so we designed and synthesized four kinds of new bivalent ionic liquids. The ionization between two molecular N-heterocyclic compound and one molecular 1,4-dibromobutane gave four kinds of bivalent ionic liquids, three of which were prepared by the treatment of 1,4-dibromobutane with morpholine, piperidine, and pyridine respectively, and the fourth one was synthesized firstly by the formation of N-methylmorpholinium cation using N-methyl morpholine and 1,4-dibromobutane following its future quaternary ammoniumization with pyridine. The melting points of dipiperidinium based salt are above 100 ℃, and the melting points of the rest are below 100 ℃. We calculated some properties of the bivalent ionic liquids, and hope that this will help the deep research on the relationship between structure and property of RTILs.

Key words: Room temperature bivalent ionic liquid, Synthesis, Structure, Property