反应详情

To a solution of 2-(4,5-diamino-1H-pyrazol-1-yl)ethanol sulfate (5 g) in water (30 ml) and dioxane (15 ml) was added aqueous sodium hydroxide solution under ice-cooling to adjust the mixture to pH 7. Phenyl chloroformate (3.42 g) was added to the mixture with controlling pH at 7, and the whole mixture was stirred at room temperature for 2 hours. The reaction mixture was extracted with ethyl acetate-tetrahydrofuran (1:1) and the extract was dried over anhydrous magnesium sulfate. Evaporation of the solvent gave a crude product of phenyl [5-amino-1-(2-hydroxyethyl)-1H-pyrazol-4-yl]carbamate as an oil, which was used for Preparation 44 without further purification.

1. temperaturecooling
2. extractionThe reaction mixture was extracted with ethyl acetate-tetrahydrofuran (1:1)
3. dry with materialthe extract was dried over anhydrous magnesium sulfate
4. customEvaporation of the solvent