Indole-2-acetic acid

21422-40-2

32588-36-6

Step 1: A solution of lithium hydroxide (346 mg, 8.25 mmol) in water (2 mL) was added to a mixture of THF (2 mL) and methanol (6 mL) of methyl 2-(1H-indol-2-yl)acetate (520 mg, 2.75 mmol) (prepared according to the method reported by Capuano et al. Chem. Ber., 1986, 119 , 2069). The reaction mixture was stirred at room temperature for 1 hour. Upon completion of the reaction, the mixture was concentrated under reduced pressure to remove the organic solvent. The residue was diluted with water (20 mL) and extracted with ether (2 x 10 mL) to remove non-polar impurities. The aqueous phase was carefully acidified to pH 2 with 1 M HCl and then extracted with dichloromethane (3 x 20 mL). The organic phases were combined, dried over anhydrous magnesium sulfate, filtered and the solvent evaporated under reduced pressure to give indole-2-acetic acid (350 mg, 72% yield) as a pink solid.