反应详情

温度

5 °C

1,3-Di-n-butylxanthine (73 g, 0.28 mol) was dissolved in acetic acid (120 ml) and then treated with concentrated nitric acid (49 g) at 87° C. After 1 hour, the mixture was cooled to 5° C., the resulting yellow precipitate filtered off and washed with water (50 ml). The yellow crystals were dissolved in dichloromethane and washed twice with water. The separated organic layer was then dried (anhydrous sodium sulphate) and concentrated to give a crystalline product, yield 73 g (86%), m.pt 168° C.

1. filtrationthe resulting yellow precipitate filtered off
2. washwashed with water (50 ml)
3. dissolutionThe yellow crystals were dissolved in dichloromethane
4. washwashed twice with water
5. dry with materialThe separated organic layer was then dried (anhydrous sodium sulphate)
6. concentrationconcentrated
7. customto give a crystalline product, yield 73 g (86%), m.pt 168° C.