反应详情

A solution of 0.2 g (0.3 mmol) of 1α,3β,25-tris[(tetrahydro-2H-pyran-2-yl)oxyl]-cholest-5-en-23-yne in 10 ml of ethanol was treated with 0.05 g of sodium hydrogen carbonate and 0.4 ml of concentrated ethanolic Raney-nickel suspension, and the mixture was shaken in a hydrogen atmosphere at normal pressure for 24 hours. The catalyst was filtered off, and the filtrate was evaporated. The residue, containing 1α,3β,25-tris[(tetrahydro-2H-pyran-2-yl)oxy]-cholest-5-ene, was dissolved in 5 ml of methanol. 10 mg of p-toluenesulphonic acid monohydrate were added. The solution was left at room temperature for 3 hours. While stirring there were added dropwise 5 ml of water, the suspension was suction filtered, and the residue was dried. There was obtained 0.11 g (89%) of 1α,3β,25-trihydroxy-cholest-5-ene which melts at 174°-176° C. after recrystallization from acetone.

1. filtrationThe catalyst was filtered off
2. customthe filtrate was evaporated
3. additionThe residue, containing 1α,3β,25-tris[(tetrahydro-2H-pyran-2-yl)oxy]-cholest-5-ene
4. dissolutionwas dissolved in 5 ml of methanol
5. addition10 mg of p-toluenesulphonic acid monohydrate were added
6. additionwere added dropwise 5 ml of water
7. filtrationsuction filtered
8. customthe residue was dried