PURPOSE: To produce the titled compound in high yield, with a simple process, by heating an easily handleable 1,1,1,3,3,3-hexafluoropropane-2,2-diol.dihydrate and a ketene-producing compound in a reaction tube heated at a specific temperature.
CONSTITUTION: The titled compound useful as an intermediate of polymer or various fluorine-containing compounds, economically, by heating 1,1,1,3,3,3- hexafluoropropnae-2,2-diol.dihydrate and a ketene-producing compound in a reaction tube maintained at 450W650°C, and washing the resultant reaction product gas with concentrated sulfuric acid to remove the organic by-products. The washing of the reaction gas with concentrated sulfuric acid results in the remarkable improvement in the purity of the titled compound without causing the loss of the compound, and exhibits remarkable effect to remove the water entrained in the reaction gas by the water-washing and/or alkali-washing treatment carried out prior to the sulfuric acid washing.
NAKAMICHI TOSHIHIRO
KATSUHARA YUTAKA
Next Patent: JPS6023335