反应详情

温度

0 °C

Crude product of 6-hydroxyindazole-3-carboxylic acid (1.504 g) which can be prepared according to the method described in Reference example 16, etc. was dissolved in ethanol, cooled to 0° C., and then thionyl chloride (7.6 mL; manufactured by Wako Pure Chemical Industries, Ltd.) was added dropwise thereto. The reaction solution was stirred overnight at 60° C. After cooling to room temperature, disappearance of the reacting material and generation of the target compound was confirmed based on LCMS. The solvent was evaporated under reduced pressure. To the residue, ethanol (50 mL) was added, and to the residue which had been obtained by evaporation of the solvent under reduced pressure, THF (50 mL) was added and the solvent was removed again by evaporation under reduced pressure to obtain the target compound as a crude product (1.457 g).

1. temperatureAfter cooling to room temperature
2. customThe solvent was evaporated under reduced pressure
3. additionTo the residue, ethanol (50 mL) was added
4. customto the residue which had been obtained by evaporation of the solvent under reduced pressure, THF (50 mL)
5. additionwas added
6. customthe solvent was removed again by evaporation under reduced pressure