Sulfuric Acid → Tetrafluorosuccinyl fluoride

Participants

Reaction Conditions

Reaction Steps

Into a four necked flask equipped with a thermometer, a reflux condenser, a dropping funnel and a magnetic stirrer, 4950 g (18.5 moles as SO3) of fuming sulfuric acid containing 30% of SO3 were charged. The flask was heated to 85° C. and then, 990 g (2.2 moles) of 1,4-diiodoperfluorobutane having the forumla I (CF2)4I were added dropwise to the flask. The reaction was conducted for 6 hours while maintaining the temperature in the reactor at 85° to 95° C. The reaction mixture discharged from the reflux condenser, was passed through a gas washing bottle containing concentrated sulfuric acid and was collected in a flask cooled with a dryice-ethanol coolant. The collected reaction products in the flask were separated by distillation whereby 247 g of a fraction of a boiling point of 18° C. were obtained. According to F19NMR analysis of the fractions, the fraction having a boiling point of 18° C. consisted of 200g (yield of 47%) of perfluoro- γ-butyrolactone and 47 g (yield of 11%) of perfluorosuccinic difluoride. Another fraction having a boiling point of 1° C., 45 g (yield of 11% ) of perfluoroetrahydrofuran was also obtained.

Provenance & Evidence