反应详情

温度

60 °C

To 5.85 g (30 m mol) of 3-hydrazino-6-morpholino-pyridazine in 130 ml of ethanol, ethyl ether (45 ml) saturated with hydrogen chloride is added. The suspension of pale yellow precipitate which forms is additioned with 12 g (90 m mol) of 2,5-dimethoxytetrahydrofuran and the mixture is refluxed (60° C.) for 6 hours. The solvent is removed under vacuum and the residue is dissolved in water, brought to pH 8 by addition of a sodium carbonate solution and extracted with four portions (each of 100 ml) of dichloromethane. The organic extracts are pooled together, washed with water (50 ml) and anhydrified over sodium sulfate. Evaporation of the solvent yields an oil which is purified through column chromatography (silicagel, 500 g) using as the eluent a mixture of dichloromethane and ethyl acetate wherein the ratio of ethyl acetate is gradually increased from 20% to 100%. Evaporation of the more polar fraction yields 0.15 g (2%) of the product of the title which melts at 228° C.

1. additionThe suspension of pale yellow precipitate which
2. customThe solvent is removed under vacuum
3. dissolutionthe residue is dissolved in water
4. additionbrought to pH 8 by addition of a sodium carbonate solution
5. extractionextracted with four portions (each of 100 ml) of dichloromethane
6. washwashed with water (50 ml)
7. customEvaporation of the solvent
8. customyields an oil which
9. customis purified through column chromatography (silicagel, 500 g)
10. additiona mixture of dichloromethane and ethyl acetate wherein the ratio of ethyl acetate
11. temperatureis gradually increased from 20% to 100%
12. customEvaporation of the more polar fraction