THE OPTIMIZATION AND THE EXAMINATION OF THE EFFECT OF IONIC LIQUIDS ON THE SYNTHESIS OF SEVOFLUORANE

Sevoflurane is a new inhalation anesthetic that because of its unique characteristics is very interesting and it's usage is developped. Different methods have been reported for its synthesis, the best one being a two- step method. In the first step, 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) reacts with AlCl 3 and trioxane to produce sevochlorane. In the second step, sevochlorane reacts with KF in PEG -400 and sevoflurane is obtained. In this research, the amounts of PEG-400, KF and reaction time have been optimized (PEG-400 to SVC (2.5:1 V/V), KF to SVC(1.2:1 mol/mol), T=90-95°C and t=2.5 h) and sevofluorane was obtained in 90% yield. Also, ionic liquids were used as green solvent. It was found out that fluorination reaction of sevochlorane with KF can also be performed in ionic liquids, but, howevere, with lower yields. The maximum yield was achieved by the use of tetrabutylammoniumfluoride ionic liquid TBAF in 20% yield.