Hydrochloric Acid → Benzyl[4-(2-aminopyridin-4-yloxy)-2-fluorophenyl]carbamate

Participants

Reaction Steps

A 4N solution of hydrochloric acid in ethyl acetate (120 ml) was cooled in an ice bath. tert-Butyl[4-(4-benzyloxycarbonylamino-3-fluorophenoxy)pyridin-2-yl]carbamate (3.92 g) was added thereto while stirring, followed by stirring in an ice bath for 10 min. The reaction mixture was then stirred at room temperature for 3.5 hr. The reaction mixture was concentrated under reduced pressure. Ethyl acetate (150 ml) and a saturated aqueous solution of sodium hydrogencarbonate (70 ml) were added thereto, and liquid-liquid separation was carried out. The aqueous layer was extracted with ethyl acetate (50 ml). The combined organic layer was washed with brine and dried over anhydrous sodium sulfate. The organic layer after drying was concentrated under reduced pressure. The resultant crystals were suspended in a mixed solvent of hexane-ethyl acetate (5:1). The crystals were collected by filtration and washed with a mixed solvent of hexane-ethyl acetate (5:1). The crystals were sucked to dryness at room temperature to provide the titled compound as pale yellow crystals (2.93 g, 95.9%).

Provenance & Evidence