tert-Butanol → HCID 90731614, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-({2-[(cyclopropylcarbonyl)amino][1,3]thiazolo[5,4-b]pyridin-5-yl}oxy)-4-methoxybenzoic acid (1.92 g, 4.98 mmol) produced in Example C4(v) in N,N-dimethylformamide (50 mL) and 2-methylpropan-2-ol (50 mL) were added triethylamine (5 mL, 35.9 mmol) and diphenylphosphoryl azide (3 mL, 13.9 mmol), and the mixture was stirred at 120° C. for 2 hr. After cooling the reaction solution to room temperature, the reaction solution was diluted with water (200 mL). The yielded solid was collected by filtration to give tert-butyl[3-({2-[(cyclopropylcarbonyl)amino][1,3]thiazolo[5,4-b]pyridin-5-yl}oxy)-4-methoxyphenyl]carbamate (primary product, 1.16 g). The filtrate was extracted with ethyl acetate-hexane (1:1, 150 mL×3), and the combined organic layer was washed with saturated brine (150 mL), and dried over anhydrous magnesium sulfate. The insoluble material was filtered off, the filtrate was concentrated under reduced pressure, and the residue was subjected to silica gel column chromatography (ethyl acetate/hexane=2/98→80/20) to give tert-butyl[3-({2-[(cyclopropylcarbonyl)amino][1,3]thiazolo[5,4-b]pyridin-5-yl}oxy)-4-methoxyphenyl]carbamate (secondary product, 994 mg). These products contained structurally unknown impurities but used for the next reaction without further purification.

Provenance & Evidence