Ionic liquids − defined as salts with a melting point below 100 ◦C – date back to 1914, when Paul Walden reported on [C2H5NH3][NO3], a salt with a melting point of +12 ◦C. While Walden was surely ahead of his time, ionic liquids made an impressive development during the last 10 years. This is due to their unique portfolio of properties: high temperature stability (in favourable cases up to 400 ...
