反应详情

The compound of Example 1A (13 g, 110 mmol) is dissolved in 400 ml tetrachloromethane, and 29.4 g (165 mmol) N-bromosuccinimide and 0.4 g (1.6 mmol) dibenzoylperoxide are added. The reaction mixture is refluxed for three hours, cooled down to room temperature and filtered. The solution is washed with aqueous sodium thiosulfate, dried over magnesium sulfate, and the solvent is removed in vacuo. The residue is dissolved in 200 ml dioxane and 200 ml water, calcium carbonate (44 g, 440 mmol) is added, and the mixture is stirred at reflux for 2 hours. After cooling down to room temperature, the mixture is filtered, and dichloromethane is added. After phase separation, the organic phase is dried over magnesium sulfate, and the solvent is removed in vacuo. The product is purified by chromatography (silica, eluent: cyclohexane/ethyl acetate 2:1).

1. temperatureThe reaction mixture is refluxed for three hours
2. filtrationfiltered
3. washThe solution is washed with aqueous sodium thiosulfate
4. dry with materialdried over magnesium sulfate
5. customthe solvent is removed in vacuo
6. dissolutionThe residue is dissolved in 200 ml dioxane
7. temperatureat reflux for 2 hours
8. temperatureAfter cooling down to room temperature
9. filtrationthe mixture is filtered
10. additiondichloromethane is added
11. customAfter phase separation
12. dry with materialthe organic phase is dried over magnesium sulfate
13. customthe solvent is removed in vacuo
14. customThe product is purified by chromatography (silica, eluent: cyclohexane/ethyl acetate 2:1)