反应详情

To a stirring suspension of sodium hydride (740 mg, 30.8 mmol) in anhydrous dimethylsulfoxide (120 ml) was added 8-bromo-3,7-dimethylxanthine (6.5 g, 25.0 mmol). After stirring at room temperature under argon for 1.5 hours, (R)-5-acetoxyhexyl-1-chlorohexane (4.91 g, 27.5 mmol) was added and the mixture was stirred at 80° C. for 18 hours. After cooling to room temperature, the reaction mixture was quenched by addition of saturated aqueous sodium chloride solution (300 ml) and extracted with ethyl acetate (3×50 ml). The combined extracts were washed with water (2×20 ml), with saturated aqueous sodium chloride solution (20 ml) and dried over magnesium sulfate. After evaporation of the solvent under reduced pressure, the crude product was purified by flash chromatography on silica gel eluting with ethyl acetate-hexane (1:1) to provide (R)-1-(5-acetoxyhexyl)-8-bromo-3,7-dimethylxanthine (7.38 g, 74% yield) as a colorless oil.

1. stirringthe mixture was stirred at 80° C. for 18 hours
2. temperatureAfter cooling to room temperature
3. customthe reaction mixture was quenched by addition of saturated aqueous sodium chloride solution (300 ml)
4. extractionextracted with ethyl acetate (3×50 ml)
5. washThe combined extracts were washed with water (2×20 ml), with saturated aqueous sodium chloride solution (20 ml)
6. dry with materialdried over magnesium sulfate
7. customAfter evaporation of the solvent under reduced pressure
8. customthe crude product was purified by flash chromatography on silica gel eluting with ethyl acetate-hexane (1:1)