Hydrochloric Acid → 5-(Tert-butoxycarbonylamino)-2-(2,6-difluoro-3-methoxyphenyl)thiazole-4-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a mixture of methyl 5-[(tert-butoxycarbonyl)amino]-2-(2,6-difluoro-3-methoxyphenyl)-1,3-thiazole-4-carboxylate (48.5 mg, 0.121 mmol) and lithium hydroxide, monohydrate (37 mg, 0.89 mmol) was added MeOH (1.5 mL), followed by water (1.5 mL). The reaction mixture was stirred at 60° C. for 3.5 h. The reaction mixture was allowed to cool to room temperature and 4.0 M hydrogen chloride in water (0.25 mL, 0.99 mmol) was added to adjust the pH to 1-2. The mixture was diluted with EtOAc (50 mL) and brine (50 mL). The aqueous layer was further extracted with EtOAc (2×50 mL). The combined organic extracts were dried over Na2SO4 and concentrated under reduced pressure to give the sub-title compound as a white solid which was used directly in the next step without further purification (52.2 mg). LCMS calc. for C16H17F2N2O5S (M+H)+: m/z=387.1. Found: 387.1.

Provenance & Evidence