Water → 7-Ethyl-1H-indole-3-carboxylic acid

Participants

Reaction Steps

To a solution of 3.0 g of 7-ethylindole in 25 mL of DMF, 3.5 mL of trifluoroacetic anhydride was added under ice cooling and the resulting mixture was stirred at room temperature for 3 hours. To the solution, 100 mL of water was added, and the precipitated solid was collected by filtration. The solid thus obtained was suspended in 100 mL of 5 M aqueous sodium hydroxide solution and the resulting suspension was stirred at 100° C. for 5 hours. After the solution was allowed to cool, it was washed twice with 30 mL of 1,2-dichloroethane. Concentrated hydrochloric acid was added to the aqueous layer to adjust the pH to pH2 and the precipitated solid was collected by filtration and washed with ether to obtain 3.14 g of 7-ethylindole-3-carboxylic acid as a beige solid.

Provenance & Evidence