tert-Butanol → Tert-butyl [4-(4-benzyloxycarbonylamino-3-fluorophenoxy)pyridin-2-yl]carbamate

Participants

Reaction Steps

Triethylamine (4.6 ml) was added to a suspension of 4-(4-benzyloxycarbonylamino-3-fluorophenoxy)pyridine-2-carboxylic acid (5.04 g) in tert-butanol (50 ml) at room temperature, and the mixture was stirred. After adding diphenylphosphoryl azide (3.13 ml) thereto at room temperature, the mixture was stirred for 30 minutes at room temperature under a nitrogen atmosphere. It was then heated and stirred at 90° C. for 30 minutes and at 100° C. for 4 hours. The reaction mixture was subsequently cooled to room temperature. Ethyl acetate (25 ml) was added thereto, and the reaction mixture was stirred for 30 minutes while cooling in an ice bath. The precipitated crystals were filtered and washed with diethyl ether. They were then subjected to aeration drying for 1 hour at room temperature to provide the title compound (3.92 g, 65.5%) as colorless crystals.

Provenance & Evidence