反应详情

To a solution of ethyl 4-cyano-1H-indole-2-carboxylate (I-3a: 330 mg, 1.542 mmol) in ethanol (10 mL) was added LiOH.H2O (129 mg, 3.08 mmol) and the mixture was refluxed for 16 h. The solvent was evaporated under reduced pressure and the residue diluted with water (10 mL). The aqueous layer was acidified with 10% aq. HCl solution to pH 6.0 and the precipitated solid was filtered. The residue was washed with water and dried under vacuum to afford 250 mg (87%) of 4-cyano-1H-indole-2-carboxylic acid (I-3b) as an off-white solid.

1. temperaturethe mixture was refluxed for 16 h
2. customThe solvent was evaporated under reduced pressure
3. additionthe residue diluted with water (10 mL)
4. filtrationthe precipitated solid was filtered
5. washThe residue was washed with water
6. customdried under vacuum