反应详情

A solution of 20-oximino-5α-pregna-2,16-diene-11-one (60 g) in anhydrous pyridine (250 ml) was treated with 225 ml of a solution prepared from phosphorus oxychloride (55 ml) in anhydrous pyridine (250 ml) whilst maintaining the reaction temperature at `5° during addition of the reagent. The reaction mixture was then added to a solution of concentrated HCl (350 ml) in water (3 l). This mixture was stirred for 60 hours before collecting the precipitate by filtration. The precipitate was washed with water, dissolved in hot industrial methylated spirits and treated with 2 N HCl (50 ml) at room temperature. After one hour, the reaction mixture was diluted with water and the precipitate obtained was collected by filtration, washed with water and dried. (38.4 g). Crystallisation from methanol afforded the title compound, m.p. 188°-192°, [α]D +207°.

1. temperaturewhilst maintaining the reaction temperature at `5°
2. additionduring addition of the reagent
3. custombefore collecting the precipitate
4. filtrationby filtration
5. washThe precipitate was washed with water
6. dissolutiondissolved in hot industrial methylated spirits
7. additiontreated with 2 N HCl (50 ml) at room temperature
8. waitAfter one hour
9. additionthe reaction mixture was diluted with water
10. customthe precipitate obtained
11. filtrationwas collected by filtration
12. washwashed with water
13. customdried
14. customCrystallisation from methanol