反应详情

To a solution of 0.10 g of lithium aluminum hydride in 5 ml of tetrahydrofuran was added 0.66 g of 1α,3β-bis(tetrahydropyran-2-yloxy)cholesta-5,7-dien-22-yl methanesulfonate under heating and the mixture was refluxed for 2 hours. The resulting reaction mixture was cooled and, then, water and diluted hydrochloric acid were added in succession. The mixture was stirred at room temperature for 2 hours. The resulting solution was diluted with water and extracted with diethyl ether. The extract was washed with diluted hydrochloric acid and aqueous sodium chloride solution and dried over anhydrous sodium sulfate. The low-boiling fraction was then distilled off and the residue was purified by silica gel column chromatography and recrystallized from methanol. The procedure yielded 0.18 g of cholesta-5,7-diene-1α,3β-diol (yield: 45%) showing the following physical properties.

1. temperatureunder heating
2. temperaturethe mixture was refluxed for 2 hours
3. customThe resulting reaction mixture
4. temperaturewas cooled
5. extractionextracted with diethyl ether
6. washThe extract was washed with diluted hydrochloric acid and aqueous sodium chloride solution
7. dry with materialdried over anhydrous sodium sulfate
8. distillationThe low-boiling fraction was then distilled off
9. customthe residue was purified by silica gel column chromatography
10. customrecrystallized from methanol