Hydrochloric Acid → 5-Fluoro-3-methyl-1H-indole-2-carboxylic acid

Participants

Reaction Steps

Ethyl 5-fluoro-3-methyl-1H-indole-2-carboxylate (8.3 g, 37.5 mmol) and potassium hydroxide (6.3 g, 112.5 mmol) in a mixture of ethanol (20 mL) and water (15 mL) was heated at reflux for 1 hour. The volume was reduced to 10 mL under reduced pressure and the solution brought to an acidic pH with a 3N aqueous solution of hydrochloric acid. The resulting precipitate was filtered, washed with water (100 mL) and dried in vacuo at 80° C. overnight to afford 5-fluoro-3-methyl-1H-indole-2-carboxylic acid as a white solid. MS (ES) m/z 192.0.

Provenance & Evidence