反应详情

To a solution in anhydrous tetrahydrofuran (10 ml) of the compound (392 mg) obtained in Example 1a, a borane-tetrahydrofuran complex (1.0 M, 2.2 ml) was added dropwise under a nitrogen atmosphere. After heating the reaction mixture under reflux for 3 hours, water was added and the mixture was concentrated at reduced pressure. Brine was added to the resulting residue and the mixture was extracted with ethyl acetate. The organic layer was dried with anhydrous sodium sulfate and concentrated at reduced pressure. The resulting residue was purified by silica gel column chromatography (eluent; ethyl acetate:dichloromethane=1:19) to give the titled compound (yield, 70%).

1. temperatureAfter heating the reaction mixture
2. temperatureunder reflux for 3 hours
3. concentrationthe mixture was concentrated at reduced pressure
4. additionBrine was added to the resulting residue
5. extractionthe mixture was extracted with ethyl acetate
6. dry with materialThe organic layer was dried with anhydrous sodium sulfate
7. concentrationconcentrated at reduced pressure
8. customThe resulting residue was purified by silica gel column chromatography (eluent; ethyl acetate:dichloromethane=1:19)