反应详情

温度

4 °C

To a mixture of the compound of part (iii) (34 kg), ethanol (170 L) and water (5 kg) was added 5% w/w palladium-on-carbon (50% w/w water content) (3.4 kg) and the mixture hydrogenated at 50° C. and 345 kPa (50 psi) until completion of the reaction. Water (10.5 L) was added and the catalyst removed by filtration. The filtrate was concentrated under reduced pressure to a small volume and extracted with dichloromethane (2×58 L). The combined organic extracts were concentrated under reduced pressure and toluene (150 L) added. The mixture was concentrated under reduced pressure to 50 L in volume, toluene (50 L) added and cooled to 4° C. for 4 hours. The precipitated product was collected by filtration, washed with toluene (10 L) and dried (Yield=20 kg), m.p. 112–4° C.

1. customthe mixture hydrogenated at 50° C. and 345 kPa (50 psi) until completion of the reaction
2. customthe catalyst removed by filtration
3. concentrationThe filtrate was concentrated under reduced pressure to a small volume
4. extractionextracted with dichloromethane (2×58 L)
5. concentrationThe combined organic extracts were concentrated under reduced pressure and toluene (150 L)
6. additionadded
7. concentrationThe mixture was concentrated under reduced pressure to 50 L in volume, toluene (50 L)
8. additionadded
9. filtrationThe precipitated product was collected by filtration
10. washwashed with toluene (10 L)
11. customdried (Yield=20 kg), m.p. 112–4° C.