4. Processes specific to ionic synthesis

Ionic solvent chemistry requires a change in the experimenter's "reflexes", and is therefore a stimulating way of exploring new processes.

For example, the simple fact that the solvent is no longer a volatile species prohibits its usual evaporation at the end of the experiment. The recovery of reaction products must therefore be approached differently. The most elegant and straightforward method, when made possible by the product's low boiling point and reasonable thermal stability, is to reverse the process, i.e. distill the product itself. R. Grée et al. have, for example, recently described the synthesis of mono- and gem-difluorinated compounds by DAST (diethylaminosulfurtrifluoride) fluorination of alcohols and ketones in [omim][PF ₆ ] medium. Distillation enables the product to be recovered in good yields, while...