反应详情

The compound (4267.9 g, 13.929 mol) obtained in Example 3, 10% palladium carbon (889.4 g, ca. 50% water-containing product) and methanol (38.4 L) were charged, and a hydrogenation reaction was conducted at normal pressure at 50° C. for 5 hrs. After the reaction, the reaction mixture was separated by filtration without cooling to remove the insoluble material and washed with methanol (3 L). The reaction mixture was concentrated under reduced pressure to about 10 L, and ethyl acetate (15 L) was added, followed by concentration again under reduced pressure to about 10 L, which step was conducted twice. The residue (ca. 10 L) was stirred under reflux for 2 hrs., and cooled to room temperature. The crystals were collected by filtration, washed with ethyl acetate (2 L) and dried in vacuo at 40° C. to give the title compound (2619.2 g, yield 86.1%) as white crystals.

1. customa hydrogenation reaction
2. customAfter the reaction
3. customthe reaction mixture was separated by filtration
4. temperaturewithout cooling
5. customto remove the insoluble material
6. washwashed with methanol (3 L)
7. concentrationThe reaction mixture was concentrated under reduced pressure to about 10 L, and ethyl acetate (15 L)
8. additionwas added
9. concentrationfollowed by concentration again under reduced pressure to about 10 L, which step
10. temperatureunder reflux for 2 hrs
11. filtrationThe crystals were collected by filtration
12. washwashed with ethyl acetate (2 L)
13. customdried in vacuo at 40° C.