反应详情

温度

80 °C

0.5 g of sodium hydride are reacted with 15 ml of anhydrous dimethyl-sulphoxide under a nitrogen atmosphere with stirring at 80° C. and cooled to 15° C. after 25 minutes. To prepare triphenyl-methylene-phosphorane, 8.1 g of methyl-triphenyl phosphonium iodide in 20 ml of anhydrous dimethyl-sulphoxide are added to this solution. After stirring for 10 minutes at room temperature, 5.6 g of 1,3-dimethyl-7-(5-oxohexyl)-xanthine in 10 ml of dimethylsulphoxide are added dropwise over 10 minutes, and the temperature is not allowed to exceed 20° C. After standing overnight, the mixture is dissolved in water, extracted with diethyl ether and the ether phase is separated and dried over Na2SO4. The product obtained after evaporation at reduced pressure is subsequently subjected to a purification by column chromatography on silica gel with methylene chloride/acetone (1:1) as eluent. The resulting product is in the form of an oil after distillation under reduced pressure. Yield: 3.5 g (63.3% of theory relative to the starting product used); refractive index: nD20 =1.5445.

1. temperaturecooled to 15° C. after 25 minutes
2. additionare added to this solution
3. stirringAfter stirring for 10 minutes at room temperature
4. customto exceed 20° C
5. extractionextracted with diethyl ether
6. customthe ether phase is separated
7. dry with materialdried over Na2SO4
8. customThe product obtained
9. customafter evaporation at reduced pressure
10. customis subsequently subjected to a purification by column chromatography on silica gel with methylene chloride/acetone (1:1) as eluent
11. distillationafter distillation under reduced pressure