Ethanol → Ethyl 5-methoxyindole-2-carboxylate

Participants

Reaction Steps

5-Methoxy-1H-indole-2-carboxylic acid (10 g, 52.3 mmol) in EtOH (400 ml) containing 36% H2SO4 (7 ml) was heated under reflux for 18 hr. After cooling the mixture was neutralised with 2N NaOH (to pH 7) and extracted with EtOAc (3×150ml), the combined extracts were washed with 10% NaHCO3 (2×25 ml), dried (MgSO4), filtered and evaporated to afford 5-methoxy-1H-indole-2-carboxylic acid ethyl ester as a brown solid (9.52 g, 43.3 mmol, 82%) Mp. 154-155° C., MS: m/e=219.1 (M+).

Provenance & Evidence