Trifluoroacetic anhydride → Methyl 6-amino-1H-indole-2-carboxylate

Participants

Reaction Steps

To 551 mg methyl 6-[(tert-butoxycarbonyl)amino]-1H-indole-2-carboxylate dissolved in 15 mL dichloromethane was added 5 mL trifluoroacetic anhydride, and the mixture stirred at room temperature for 1.5 h. P The mixture was partitioned between dichloromethane and 1 N sodium hydroxide until neutral, dried over magnesium sulfate and concentrated. Obtained 360 mg of the crude methyl 6-amino-1H-indole-2-carboxylate. To 200 mg (1.05 mmol) of crude product dissolved in 5 mL dichloromethane and 340 □L pyridine at 0° C. was added 81 □L methanesulfonyl chloride. The mixture was stirred at 0° C. for 1 h, was partitioned between dichloromethane and 1 N hydrochloric acid until neutral, was dried over magnesium sulfate and concentrated to obtain 333 mg of methyl 6-[(methylsulfonyl)amino]-1H-indole-2-carboxylate as crude product.

Provenance & Evidence