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 re-dissolved 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 re-dissolved 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