Sodium Hydroxide → 5-((tert-Butoxycarbonyl)amino)-3-methylthiophene-2-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

The compound (1.81 g, 6.68 mmol) obtained in Example 30b was dissolved in methanol (27 mL), a 1 N aqueous sodium hydroxide solution (26.7 mL, 26.7 mmol) was added, and the mixture was stirred at 50° C. for 19.5 hours. A 1 N aqueous sodium hydroxide solution (26.7 mL, 26.7 mmol) was added to the reaction mixture, and the mixture was stirred at 50° C. for 24 hours. Methanol was evaporated under reduced pressure, water and ethyl acetate were added to the resulting residue, and the mixture was extracted with water (×2). The resulting aqueous layer was adjusted to pH 1 with 1 N hydrochloric acid, the mixture was extracted with ethyl acetate (×2), and then the organic layer was washed with saturated sodium chloride solution. The organic layer was dried with anhydrous sodium sulfate, the solvent was evaporated under reduced pressure, and moisture was removed from the resulting residue azeotropically with toluene (×2) to give the title compound (1.23 g; yield, 62%) as a white solid.

Provenance & Evidence