反应详情

3 g of 5-bromo-1H-indazole-3-carboxylic acid was dissolved in 60 mL of ethanol, added with 0.6 mL of concentrated sulfuric acid, and heated under reflux for 8 hours. After allowing to cool to room temperature, addition of water and extraction with ethyl acetate were conducted, and the resultant organic layer was washed with saturated aqueous sodium hydrogen carbonate and saturated brine, dried over magnesium sulfate, and the solvent was evaporated, to afford 2.7 g of the title compound as yellow crystals.

1. temperatureheated
2. temperatureunder reflux for 8 hours
3. washthe resultant organic layer was washed with saturated aqueous sodium hydrogen carbonate and saturated brine
4. dry with materialdried over magnesium sulfate
5. customthe solvent was evaporated