Dimethylformamide → 2H-Perfluoroisopropyl 2-fluoroacrylate

Participants

Reaction Conditions

Reaction Steps

A 2-Liter glass flask which had been equipped with a thermometer, a stirrer, a reflux condenser and a dropping funnel was charged with 1.2 l of o-xylene, 29 g (0.4 mol) of dimethylformamide and 200 g (1.87 mol) of ammonium α-fluoroacrylate. To this initial charge were then added dropwise in the course of 1 hour 238 g (2.0 mol) of thionyl chloride. The reaction mixture was then maintained at a temperature of 80° C. for 2 hours. After subsequently cooling down to a temperature of 0° C., the mixture had added to it a mixture of 202 g (2 mol) of triethylamine and 336 g (2 mol) of hexafluoroisopropanol in the course of 30 minutes. The resulting mixture was stirred for a further 30 minutes, and the resulting precipitate was filtered off. The filtrate was treated with 1 g of hydroquinone monomethyl ether and rapidly distilled under a pressure of 266 mbar. The fraction obtained within the temperature range from 45° to 85° C. was washed with hydrochloric acid (2.4 molar) and with water, was dried and was distilled again, giving 232 g (52 percent of theory) of pure hexafluoroisopropyl α-fluoroacrylate. This ester was a colorless liquid with a refractive index nD23 =1.3145, a boiling point of 46.8° C. (at 213 mbar) and a density of 1.453 g/cm3 (at 25° C.). In the wavelength range from 380 to 680 nm this ester had an average transmission of more than 99 percent.

Provenance & Evidence