反应详情

温度

10 °C

100 ml of an ethanol solution containing 2.5 g of sodium borohydride was added dropwise under agitation to 110 ml of methanol containing 4.9 g of calcium chloride, which was cooled below - 10° C. The mixture was agitated for 20 minutes while maintaining the temperature at about -10° C. Then, 100 ml of the ether solution containing crude cholesta-1,5,7-trien-3-on-25-ol, which was prepared in (1.) above, was added dropwise to the above mixture. The reaction mixture was further agitated at -10° C. for 1 hour and at 0° C. for 1 hour, and was then neutralized with 10% acetic acid after which the solvent was distilled off under reduced pressure. The residue was extracted with methylene chloride and the extract was washed with water and dried with magnesium sulfate. Methylene chloride was distilled off to obtain crude cholesta-1,5,7-triene-3β,25-diol (about 1 g).

1. temperaturewhile maintaining the temperature at about -10° C
2. customwas prepared in (1.) above,
3. additionwas added dropwise to the above mixture
4. stirringThe reaction mixture was further agitated at -10° C. for 1 hour and at 0° C. for 1 hour
5. distillationwas distilled off under reduced pressure
6. extractionThe residue was extracted with methylene chloride
7. washthe extract was washed with water
8. dry with materialdried with magnesium sulfate
9. distillationMethylene chloride was distilled off