Hydrochloric Acid → 1-ethyl-1H-indole-3-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

In THF (9.0 ml) was dissolved the methyl 1-ethylindole-3-carboxylate obtained in the above-described (Step 1). To the resulting solution was added 0.25N NaOH (9.0 ml) at room temperature. After the reaction mixture was stirred at 50° C. for 36 hours, 1N NaOH (1.0 ml) was added thereto, followed by stirring at 70° C. for 9 hours. The reaction mixture was cooled to room temperature, and then neutralized with 1N HCl (4.5 ml). The crystals thus precipitated were collected by filtration under reduced pressure, washed with water and dried under reduced pressure to give 1-ethylindole-3-carboxylic acid (388.0 mg, 90%, yield of 2 steps) as a pale pink amorphous substance.

Provenance & Evidence