Citric Acid → Indole-2-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

The above indole-2-carboxylic acid ethyl ester intermediate was dissolved in THF/MeOH/H2O (3:1:1) and 1 mL of 1N KOH solution. The mixture was heated at 60° C. for 4 h. The mixture was then cooled to 0° C. and acidified with 10% citric acid to about pH 4. The mixture was extracted with EtOAc, dried and concentrated to afford 0.32 g of the indole-2-carboxylic acid intermediate.

Provenance & Evidence