Room-Temperature Zwitterionic Ionic Liquids

A novel series of zwitterionic ionic liquids based on (E) or (Z) isomer of an urocanic moiety containing a carboxylate group have been prepared. All synthesized compounds present melting points below 100°C. This value can be easily tuned by changing the length of alkyl chain grafted on the imidazolium moiety and the nature of isomer.  Hence, melting temperature as low as -20°C was obtained for Z isomer with a N1, N3-methyloctyl imidazolium moiety.