Hydrochloric Acid → methyl 2-hydroxy-3-(1H-indole-2-carboxamido)benzoate

Participants

Reaction Steps

To a solution of 1H-indole-2-carboxylic acid (965 mg, 1.2 mmol) in DMF (15 mL) was added HOBt (740 mg, 1.1 mmol), DIPEA (1.98 g, 3.0 mmol) and EDCI (1.05 g, 1.1 mmol). The mixture was stirred at room temperature for 30 min. Then methyl 3-amino-2-hydroxybenzoate (835 mg, 1 mmol) was added. The mixture was stirred at room temperature for 10 hr. To the resulting mixture, water (10 mL) and aqueous hydrochloric acid (1 N) were added to pH=3, then extracted with ethyl acetate (100 mL×4). The organic phase was washed with saturated sodium bicarbonate solution and brine, dried by anhydrous sodium sulfate and concentrated to yield the crude product. The crude product was purified by column chromatography (silica gel, petroleum ether:ethyl acetate 20:1) to obtain methyl 2-hydroxy-3-(1H-indole-2-carboxamido)benzoate as a solid (530 mg, yield 26%). LC-MS (ESI) m/z 296 [M+1]−.

Provenance & Evidence