反应详情

2β-(2'-Chloroethoxy)-3α-hydroxy-5α-pregnane-11,20-dione (600 mg.) was dissolved in benzene (50 ml.), ethylene glycol (5 ml.) and toluene-p-sulphonic acid (2 mg.) added, and the vigorously stirred mixture refluxed under a Dean and Stark head for 20 hours. The cooled mixture was washed with sodium bicarbonate solution (5 ml.), water (2 × 100 ml.) and dried over anhydrous sodium sulphate. The dried solution was evaporated in vacuo to give the title compound (605 mg.) as a pale yellow foam, [α]D + 47.2° (c 1.11).

1. temperaturethe vigorously stirred mixture refluxed under a Dean and Stark head for 20 hours
2. washThe cooled mixture was washed with sodium bicarbonate solution (5 ml.), water (2 × 100 ml.)
3. dry with materialdried over anhydrous sodium sulphate
4. customThe dried solution was evaporated in vacuo