2,2,3,3,5,5,6,6-octafluoro-4-(trifluoromethyl)morpholine

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 253 g. (0.85 mol) of perfluoro-(N-methyl-morpholine) in a 300 ml. autoclave is added 72 g. (0.9 mol) of sulfur trioxide. The vessel is sealed, heated and rocked at 120° C. for 6 hrs. The autoclave is then cooled to 25° C., vented to release volatile materials and the residue charged to a 500 cc. flask equipped with magnetic stirrer, dropping funnel, condenser and thermometer. A solution of 195 g. of 96% sulfuric acid and 5 g. of H2C is added dropwise with stirring. The temperature is kept below 50° C. After the sulfuric acid is added the mixture is heated and stirred at reflux (55°-60° C.) for four hours. Distillation yields a large fraction, 207 g., b.p. 48°-65° C./740 mm., which consists of 45% by weight perfluoror-N-methyl-3-oxo-morpholine (40% conversion) and 15% by weight of higher boiling products believed to include perfluoro-(N-methyl-3,5dioxo-morpholine). Isolation of the pure amide (b.p. 59°-60° C./740 mm.) can be accomplished by distillation through a 25-plate column. autoclave is added 72 g The vessel is sealed heated the residue charged to a 500 cc flask equipped with magnetic stirrer of H2C is added dropwise is kept below 50° C is heated stirred at reflux (55°-60° C.) for four hours Distillation yields a large fraction, 207 g Isolation of the pure amide (b.p. 59°-60° C./740 mm.) can be accomplished by distillation through a 25-plate column