4-Hydroxybenzenesulfonic acid → 1,2-Bis-(4-sulphophenoxy)-3,3,4,4,5,5-hexafluorocyclopent-1-ene

Participants

Reaction Conditions

Reaction Steps

43.2 (0.3 mol) of 4-hydroxybenzenesulphonic acid (as a 65% strength aqueous solution) and 60.6 g (0.6 mol) of triethylamine were initially introduced at 5° C. in 200 ml of dimethylformamide. 31.8 g (0.15 mol) of perfluorocyclopentene were added dropwise in the course of 15 minutes and the mixture was subsequently stirred at 60° C. for 17 hours. 200 ml of methylene chloride were then added, and the reaction mixture was washed with 200 ml of water, then with 200 ml of 10% strength by weight hydrochloric acid and then again with 200 ml of water and dried. After stripping off the solvent on a rotary evaporator, 47.5 g of an oily crystalline residue remained, which was recrystallized from glacial acetic acid. 27.5 g of crystalline product having a melting point of 251° to 255° C. were obtained, which corresponds point of 251° to 255° C. were obtained, which corresponds to 35.3% of theory. A further 35 g of crude product were isolated from the washing water after acidification and concentration. The mass spectrum of the recrystallized material showed a value for m/e of 520 for the molecular ion.

Provenance & Evidence