反应详情

To a solution of 5-nitro-1H-pyrazole-3-carboxylic acid (4.88 g, 31.1 mmol) in anhydrous methanol (50 ml) at to 0° C. was added thionyl chloride (9.61 g, 5.9 ml, 80.8 mmol) drop wise. The resulting solution was heated to reflux for 2 h. The cooled solution was evaporated to dryness to give 5-nitro-2H-pyrazole-3-carboxylic acid methyl ester (4.58 g, 86%) as a off-white solid.

1. temperatureThe resulting solution was heated
2. temperatureto reflux for 2 h
3. customThe cooled solution was evaporated to dryness