反应详情

温度

80 °C

To a stirring solution of 1,7-dimethylxanthine (0.30 g, 1.67 mmol) in dimethylsulfoxide (20 ml) was added sodium hydride (42 mmg, 1.75 mmol) in one portion. After stirring for 30 minutes, (R)-5-acetoxy-1-bromohexane (0.31 g, 1.75 mmol) was added next. (R)-5-Acetoxy-1-bromohexane was prepared according to methods described in U.S. patent application Ser. No. 09/002,345, which is incorporated herein by reference. After heating at 80° C. for 18 hours, water (25 ml) was added and the aqueous solution was extracted with dichloromethane (3×20 ml). The combined extracts were washed with saturated aqueous sodium chloride solution (50 ml), dried over sodium sulfate and concentrated under reduced pressure. The residue was purified by flash chromatography on silica eluting with ethyl acetate to give (R)-3-(5-acetoxyhexyl)-1,7-dimethylxanthine (0.34 g, 64%, yield) as a colorless oil.

1. extractionthe aqueous solution was extracted with dichloromethane (3×20 ml)
2. washThe combined extracts were washed with saturated aqueous sodium chloride solution (50 ml)
3. dry with materialdried over sodium sulfate
4. concentrationconcentrated under reduced pressure
5. customThe residue was purified by flash chromatography on silica eluting with ethyl acetate