反应详情

A mixture of the product of (B) above (1.0 g) and stannous chloride dihydrate (6.07 g) in ethanol (100 ml) was heated under reflux for 8 hours and then evaporated. An excess of 20% aqueous sodium hydroxide solution was added and the mixture was extracted several times with dichloromethane. The combined organic extracts were washed with water, dried (Na2SO4) and evaporated to give an oil which was chromatographed on silica gel. Elution with dichloromethane/methanol (99:1) gave impurity and then further elution with dichloromethane/methanol (98:2) gave, after collection and evaporation of appropriate fractions, the product as an oil (0.30 g) which was used immediately in the procedure of Example 6.

1. temperaturewas heated
2. temperatureunder reflux for 8 hours
3. customevaporated
4. additionAn excess of 20% aqueous sodium hydroxide solution was added
5. extractionthe mixture was extracted several times with dichloromethane
6. washThe combined organic extracts were washed with water
7. dry with materialdried (Na2SO4)
8. customevaporated
9. customto give an oil which
10. customwas chromatographed on silica gel
11. washElution with dichloromethane/methanol (99:1)
12. customgave impurity
13. washfurther elution with dichloromethane/methanol (98:2)
14. customgave
15. customafter collection and evaporation of appropriate fractions