反应详情

181.1 g of the compound of Step A above in 500 ml of hydrobromic acid are heated at 110-120° C. for 2 hours. The mixture is then concentrated under reduced pressure, and the residue is diluted with water and extracted with diethyl ether. The aqueous phase is concentrated and 600 ml of absolute ethanol are added to the residue. 60 ml of previously cooled propylene oxide are slowly added to the reaction mixture, which is held at 0° C. The expected product which precipitates out on cooling is filtered off, washed with diethyl ether and then dried.

1. concentrationThe mixture is then concentrated under reduced pressure
2. additionthe residue is diluted with water
3. extractionextracted with diethyl ether
4. concentrationThe aqueous phase is concentrated
5. addition600 ml of absolute ethanol are added to the residue
6. addition60 ml of previously cooled propylene oxide are slowly added to the reaction mixture, which
7. customis held at 0° C
8. customThe expected product which precipitates out
9. temperatureon cooling
10. filtrationis filtered off
11. washwashed with diethyl ether
12. customdried