反应详情

Acetyl chloride (50 mL) was added dropwise to ethanol (450 mL) at 0° C. with stirring. After addition was complete, the ice-bath was removed, and the mixture was stirred at room temperature for 30 minutes. To this mixture was added 4-nitro-1H-pyrazole-3-carboxylic acid (Aldrich) (10 g, 63.65 mmol), and the resulting homogeneous mixture was stirred at room temperature for a total of 48 hours. The reaction was monitored by TLC. The solvent was removed under reduced pressure and then co-evaporated with ethyl acetate four times. The residue was concentrated under high vacuum to give the title compound as a white powder (11.426 g, (M−H)+=184, M.P.=128.0-130.1° C.).

1. additionAfter addition
2. customthe ice-bath was removed
3. stirringthe mixture was stirred at room temperature for 30 minutes
4. stirringthe resulting homogeneous mixture was stirred at room temperature for a total of 48 hours
5. customThe solvent was removed under reduced pressure
6. concentrationThe residue was concentrated under high vacuum