Dimethylformamide → 3alpha-Hydroxy-5alpha-pregn-16-ene-11,20-dione

A stirred mixture of 3β-toluene-p-sulphonyloxy-5α-pregn-16-ene-11,20-dione (627 g.), potassium acetate (918 g.), dimethylformamide (4.25 l.) and water (425 ml.) was heated on the steam bath for 4 hr. Most of the dimethylformamide was removed under reduced pressure and water was added to the residue with stirring. The solid (420 g.) was collected, washed and dried at 40° in vacuo. This material in peroxide free dioxan (7 l.) was flushed with nitrogen and a solution of potassium hydroxide (200 g.) in water (2 l.) was added. The mixture was stirred and heated at 50°-60° for 7 hr. and then left at room temperature overnight. Acetic acid (50 ml.) was added and the precipitated solid was filtered off, washed with water and dried. The dry solid was heated under reflux with benzene (2 l.) for 2 hr. the mixture cooled and filtered to give 3α-hydroxy-5α-pregn-16-ene-11,20-dione (215 g.).

1. temperaturewas heated on the steam bath for 4 hr
2. customMost of the dimethylformamide was removed under reduced pressure and water
3. additionwas added to the residue
4. customThe solid (420 g.) was collected
5. washwashed
6. customdried at 40° in vacuo
7. customThis material in peroxide free dioxan (7 l.) was flushed with nitrogen
8. additiona solution of potassium hydroxide (200 g.) in water (2 l.) was added
9. stirringThe mixture was stirred
10. temperatureheated at 50°-60° for 7 hr
11. additionAcetic acid (50 ml.) was added
12. filtrationthe precipitated solid was filtered off
13. washwashed with water
14. customdried
15. temperatureThe dry solid was heated
16. temperatureunder reflux with benzene (2 l.) for 2 hr
17. temperaturethe mixture cooled
18. filtrationfiltered

ORD-Eintrag

ord-fa3c22caebc443b8aa1263b07616067d

Quelldatensatz

uspto-grants-1976_04

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US03952031