反应详情

a dry 1-l. four-necked round-bottomed flask is equipped with a thermometer (-100° to 50°), a solid carbon dioxide-cooled reflux condenser (protected from the atmosphere through a drying tube), a gas inlet tube above the liquid level, and a magnetic stirrer. The apparatus is flushed with dry nitrogen, and 300 ml of trichlorofluoromethane is added to the flask. As the nitrogen atmosphere is maintained, the trichlorofluoromethane is cooled to -70° by means of a solid carbon dioxide-acetone bath and 119 g (1.1 mole) of sulfur tetrafluoride is added from a cylinder through the gas inlet tube. The gas inlet tube is then replaced with a 250-ml pressure-equalized dropping funnel charged with a solution of 145 g (1 mole) of N,N-diethylaminotrimethylsilane in 90 ml trichlorofluoromethane. This solution is added dropwise, with stirring, to the sulfur tetrafluoride solution at a rate slow enough to keep the temperature of the reaction mixture below -60° (about 40 minutes). The cooling bath is removed, and the reaction mixture is allowed to warm spontaneously to room temperature. The condenser is replaced with a simple distillation head, and the solvent (bp 24°) and by-product fluorotrimethylsilane (bp 17°) are distilled off into a well cooled receiver by warming the reaction mixture gently to 45° by means of a heating mantle. The yellow to dark brown residual liquid is transferred and distilled at reduced pressure through a spinning band column to give 129-145 g (80-90%) of diethylaminosulfur trifluoride as a light yellow liquid, bp 46-47 (10 mm).

1. customfour-necked round-bottomed flask is equipped with a thermometer (-100° to 50°)
2. temperaturereflux condenser (
3. customprotected from the atmosphere through a drying tube
4. customThe apparatus is flushed with dry nitrogen, and 300 ml of trichlorofluoromethane
5. additionis added to the flask
6. temperatureAs the nitrogen atmosphere is maintained
7. temperaturethe trichlorofluoromethane is cooled to -70° by means of a solid carbon dioxide-acetone bath
8. additionThis solution is added dropwise
9. customthe temperature of the reaction mixture below -60° (about 40 minutes)
10. customThe cooling bath is removed
11. distillationthe solvent (bp 24°) and by-product fluorotrimethylsilane (bp 17°) are distilled off into a well cooled receiver
12. temperatureby warming the reaction mixture gently to 45° by means of a heating mantle
13. distillationdistilled at reduced pressure through a spinning band column