反应详情

温度

50 °C

Ethyl 4-bromo-5-hydroxyindole-2-carboxylate (1.49 g, 5 mmol.), (Jnl. Org. Chem. 1984, 49, 4761), was dissolved in ethanol (10 ml) and water (3.5 ml). Potassium hydroxide (840 mg) was added and the mixture stirred at 50° C. under an atmosphere of nitrogen for 1 hour then cooled to ambient temperature. The solvent was evaporated and the residue redissolved in water (25 ml). 2M Aqueous hydrochloric acid was added until the reaction mixture was at pH4, giving a precipitate which was filtered off, washed with water and dried under vacuum to give 4-bromo-5-methoxyindole-2-carboxylic acid (1.30, 96%).

1. temperaturethen cooled to ambient temperature
2. customThe solvent was evaporated
3. dissolutionthe residue redissolved in water (25 ml)
4. addition2M Aqueous hydrochloric acid was added until the reaction mixture
5. customgiving a precipitate which
6. filtrationwas filtered off
7. washwashed with water
8. customdried under vacuum