反应详情

温度

50 °C

To a suitable reactor is charged 120 L of water, 32 kg of 50% aqueous sodium hydroxide solution, 21 L of methanol, and 70 kg of ethyl 1-cyanocyclohexaneacetate. This mixture is stirred at 50° C. for 1 hour, after which 40 to 60 L of solvent is removed by vacuum distillation while maintaining a temperature of below 50° C. After cooling to 20° to 25° C., the reaction mixture is filtered through a 0.45 micron Pall filter. The filtered solution is then diluted with 70 L of water and extracted with 20 L of methylene chloride, followed by a second extraction with 15 L of methylene chloride. The aqueous solution is charged to a pH of 8 with hydrochloric acid solution. About 6 to 8 kg of 37% hydrochloric acid solution is required. The solution is then extracted two times with 20 L each of methylene chloride. After the final extraction, the aqueous solution is stirred under full vacuum at 20° to 30° C. for 30 minutes minimum, then cooled to 3° to 10° C. While maintaining this temperature, 37% hydrochloric acid solution is charged to a pH of 3. About 32 to 36 kg of 37% hydrochloric acid solution is required. After the addition is complete, the product slurry is stirred at 3° to 10° C. for 30 minutes. The product is then collected on a centrifuge and washed with 300 to 400 L of water which is prechilled to 5° C. or less. The product is spun as dry as possible on the centrifuge and is then removed from the centrifuge and stored as a wet cake in a cold room at 5° C. or less. After vacuum drying at 40° C. for 24 hours 1-cyanocyclohexaneacetic acid is obtained; mp 103°-105° C.

1. customafter which 40 to 60 L of solvent is removed by vacuum distillation
2. temperaturewhile maintaining a temperature of below 50° C
3. temperatureAfter cooling to 20° to 25° C.
4. filtrationthe reaction mixture is filtered through a 0.45 micron Pall
5. filtrationfilter
6. additionThe filtered solution is then diluted with 70 L of water
7. extractionextracted with 20 L of methylene chloride
8. extractionfollowed by a second extraction with 15 L of methylene chloride
9. additionThe aqueous solution is charged to a pH of 8 with hydrochloric acid solution
10. extractionThe solution is then extracted two times with 20 L each of methylene chloride
11. extractionAfter the final extraction
12. stirringthe aqueous solution is stirred under full vacuum at 20° to 30° C. for 30 minutes minimum
13. temperaturecooled to 3° to 10° C
14. temperatureWhile maintaining this temperature, 37% hydrochloric acid solution
15. additionis charged to a pH of 3
16. additionAfter the addition
17. stirringthe product slurry is stirred at 3° to 10° C. for 30 minutes
18. customThe product is then collected on a centrifuge
19. washwashed with 300 to 400 L of water which
20. customis prechilled to 5° C. or less
21. customas dry as possible on the centrifuge
22. customis then removed from the centrifuge
23. customstored as a wet cake in a cold room at 5° C. or less
24. dry with materialAfter vacuum drying at 40° C. for 24 hours 1-cyanocyclohexaneacetic acid
25. customis obtained