反应详情

1.9 g (14.08 mmol) of potassium carbonate were added at 60° C. to a suspension of 2.25 g (8.8 mmol) of 7-benzyl-3-methylxanthine (prepared according to Example 1 a) in 50 ml of N-methylpyrrolidone and the mixture was stirred at this temperature for one hour. 1.4 g (11.44 mmol) of isobutoxymethyl chloride were then added dropwise and the mixture was stirred at 80° C. for 3 hours. A further 0.5 g (4.4 mmol) of isobutoxymethyl chloride was then added and the mixture was stirred again for 2 hours. 50 ml of water were then added and the mixture was extracted three times using 60 ml of methyl tert-butyl ether each time. The combined organic phases were washed twice with 30 ml of water each time, dried using magnesium sulfate and concentrated under reduced pressure. The crude product was purified by flash chromatography on a silica gel column, dichloromethane/methanol (19/0.2).

1. customprepared
2. stirringthe mixture was stirred at 80° C. for 3 hours
3. stirringthe mixture was stirred again for 2 hours
4. extractionthe mixture was extracted three times
5. washThe combined organic phases were washed twice with 30 ml of water each time
6. customdried
7. concentrationconcentrated under reduced pressure
8. customThe crude product was purified by flash chromatography on a silica gel column, dichloromethane/methanol (19/0.2)