反应详情

温度

13 °C

A mixture of 1-methyl-1H-pyrazole-4-carboxylic acid (5.0 g, 39.6 mmol), N,O-dimethylhydroxylamine hydrochloride (4.8 g, 48.0 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (9.2 g, 48.0 mmol), hydroxybenzotriazole (6.5 g, 48.0 mmol) and triethylamine (12.1 g, 120 mmol) in dichloromethane (100 mL) was stirred at 9-17° C. overnight. The reaction mixture was diluted with water (50 mL) and the resulting mixture was extracted with EtOAc (30 mL×3), the combined organic layers were washed with brine (50 mL) and dried over anhydrous Na2SO4, filtered and concentrated in vacuo (an example of a standard aqueous/EtOAc procedure), then purified by silica gel column chromatography (PE:EtOAc=5:1) to give product (4.6 g, yield 69%).

1. extractionthe resulting mixture was extracted with EtOAc (30 mL×3)
2. washthe combined organic layers were washed with brine (50 mL)
3. dry with materialdried over anhydrous Na2SO4
4. filtrationfiltered
5. concentrationconcentrated in vacuo (an example of a standard aqueous/EtOAc procedure),
6. customthen purified by silica gel column chromatography (PE:EtOAc=5:1)