An efficient and environmentally friendly synthesis of the inhalation anesthetic sevoflurane

We report a new, high yield, single vessel synthesis of the general anesthetic sevoflurane. The new synthesis consists of a two-stage fluoromethylation of hexafluoroisopropanol. In the first stage, hexafluoroisopropanol is chloromethylated using aluminum trichloride and trioxane. In the second stage fluorine exchange is carried out using potassium fluoride and poly(ethylene glycol). Sevoflurane is distilled directly from the reaction vessel yielding material of 99.95% purity. The overall yield of the process is 65–70%.