反应详情

A solution of chloroiridic acid (10 mg.) and trimethyl phosphite (1.5 ml.) in aqueous 90% isopropanol (20 ml.) was heated under reflux for 17 hours. The solution was then neutralised with triethylamine, 20,20-ethylenedioxy-2β-methyl-5α-pregnane-3,11-dione (0.66 g.) was added, and the mixture was heated under reflux for 48 hr. The reaction mixture was cooled and partitioned between methylene chloride and water. The organic layer was dried (MgSO4) and evaporated in vacuo. The residue (0.69 g.) was purified by preparative layer chromatography and crystallised from methyl acetate/petroleum ether (b.p. 60°-80°) to give 20,20-ethylenedioxy-3α-hydroxy-2α-methyl-5α-pregnan-11-one (0.42 g.), m.p. 167°-168°, [α]D + 68°.

1. temperatureunder reflux for 17 hours
2. additionwas added
3. temperaturethe mixture was heated
4. temperatureunder reflux for 48 hr
5. temperatureThe reaction mixture was cooled
6. custompartitioned between methylene chloride and water
7. dry with materialThe organic layer was dried (MgSO4)
8. customevaporated in vacuo
9. customThe residue (0.69 g.) was purified by preparative layer chromatography
10. customcrystallised from methyl acetate/petroleum ether (b.p. 60°-80°)