反应详情

A mixture of potassium carbonate (152.2 g) and de-mineralized water (300 ml) was stirred for 10 to 15 minutes to dissolve the solid. The temperature of the mixture was maintained at 30° to 35° C. and dichloromethane (300 ml) was added. L-Valine benzyl ester tosylate (153.3 g), tetrabutyl ammonium bromide (10.0 g) and 4-bromomethyl-2′-cyanobiphenyl (100 g) were added to the reaction mixture. The reaction mixture was stirred for 20 to 24 hours at 30° to 35° C. After completion of the reaction de-mineralized water (400 ml) was added and the mixture was stirred for 5 minutes. The two phases were separated and the aqueous layer was extracted with dichloromethane (200 ml). The combined organic layer was washed with de-mineralized water (300 ml) and concentrated at 40° to 45° C. Ethyl acetate (600 ml) was then added to the residue and stirred for 5 to 10 minutes to dissolve the residue. The reaction mixture was cooled to 0° to 5° C. and concentrated hydrochloric acid (50 ml) was added to the reaction mixture. The mixture was stirred for 1 hour. The precipitated solid was filtered, washed with ethyl acetate and dried to obtain the title compound.

1. dissolutionto dissolve the solid
2. temperatureThe temperature of the mixture was maintained at 30° to 35° C.
3. stirringThe reaction mixture was stirred for 20 to 24 hours at 30° to 35° C
4. stirringthe mixture was stirred for 5 minutes
5. customThe two phases were separated
6. extractionthe aqueous layer was extracted with dichloromethane (200 ml)
7. washThe combined organic layer was washed with de-mineralized water (300 ml)
8. concentrationconcentrated at 40° to 45° C
9. additionEthyl acetate (600 ml) was then added to the residue
10. stirringstirred for 5 to 10 minutes
11. dissolutionto dissolve the residue
12. temperatureThe reaction mixture was cooled to 0° to 5° C.
13. additionconcentrated hydrochloric acid (50 ml) was added to the reaction mixture
14. stirringThe mixture was stirred for 1 hour
15. filtrationThe precipitated solid was filtered
16. washwashed with ethyl acetate
17. customdried