Sodium Hydroxide → 2-Oxindole-5-carboxylic acid

Participants

Reaction Steps

5-Methoxycarbonyl-2-oxindole (1 g) and 1 g of sodium hydroxide in 20 mL of methanol was refluxed for 3 hours. The reaction mixture was cooled and concentrated to dryness. The residue was dissolved in water and extracted twice with ethyl acetate. The aqueous layer was acidified with 6 N hydrochloric acid and the precipitated solid collected, washed with water, and dried to give 0.7 g (78%) of the title compound as an off-white solid.

Provenance & Evidence