反应详情

温度

-60 °C

A solution of 600 ml. of methylene chloride and 4 grams (0.01 moles) of Aliquat 336 was charged into a 2 1. 3-neck round bottom flask and cooled to approximately -60° C. with a dry ice/acetone bath. An aqueous solution of 120 grams (2.45 moles) of sodium cyanide in 250 ml. of water was added dropwise to the reaction mixture to provide a slurry of reactants. Next, 385.38 grams (2.0 moles) of 2-ethylhexyl chloroformate was added to the mixture while maintaining the temperature below approximately -40° C. The external cooling was then removed from the reaction flask and the mixture was allowed to warm slowly. After 19 minutes the mixture had warmed to -25° C. and the external cooling was replaced. After 9 more minutes the temperature of the reaction mixture was -17° C. at which point 100 ml. of water, 200 ml. of carbon tetrachloride and 100 ml. of ice was added and the layers were allowed to separate. The organic phase was separated, and the aqueous phase was extracted twice with methylene chloride. The organic extracts were combined and dried over anhydrous magnesium sulfate. The organic phase was concentrated under reduced pressure and the residue was distilled under vacuum to provide 347.85 grams of 99.7% pure 2-ethylhexyl cyanoformate (94.9% yield). bp=95° C. (12- 15 mm).

1. customto provide a slurry of reactants
2. temperaturewhile maintaining the temperature below approximately -40° C
3. temperatureThe external cooling
4. customwas then removed from the reaction flask
5. temperatureto warm slowly
6. temperatureAfter 19 minutes the mixture had warmed to -25° C.
7. temperaturethe external cooling
8. customwas -17° C. at which
9. additionof ice was added
10. customto separate
11. customThe organic phase was separated
12. extractionthe aqueous phase was extracted twice with methylene chloride
13. dry with materialdried over anhydrous magnesium sulfate
14. concentrationThe organic phase was concentrated under reduced pressure
15. distillationthe residue was distilled under vacuum