Indoklon ,Ohio Medical, US ,1964
Bis(2,2,2-trifluoroethyl) ether was used to diminish self-discharge of Li-S cells having both low- and high-sulfur-loading sulfur cathodes.
23 parts of sodium metal were placed in 300 parts of dry dioxane in a reactor equipped with an agitator and reflux condenser. The dioxane was heated to reflux while stirring.150 parts of 2,2,2-trifluoroethanol were added very slowly in the period of about 1 hour, or until the sodium was all reacted, to form sodium 2,2,2-trifluoroethylate. 250 parts of 2,2,2-trifluoroethyl ptoluenesulfonate prepared by reacting 2,2,2-trifluoroethanol with p
Flurothyl toluenesulfonyl chloride were placed in another reactor and heated to about 160° to 185°C. The solution of sodium 2,2,2-trifluoroethylate in dioxane was added very slowly over a period of about 1? hours. Bis(2,2,2-trifluoroethyl) ether formed continuously and distilled from the reactor with the dioxane into a cooled receiving vessel. The condensed effluent from the reactor was fractionally distilled, yielding 46.5 parts of products boiling at 55° to 73°C.
The crude product was washed successively with concentrated HCl, 62% H2SO4,concentrated H2SO4 and 5% NaOH solution. It was dehydrated over a drying agent and then refractionated in a still. 20 parts of bis(2,2,2trifluoroethyl) ether were recovered (BP 62.5° to 63.5°C).
