Phosgene → 1-(3-Tert-butyl-1-phenyl-1H-pyrazol-5-yl)-3-(2-fluoro-4-(1-N-methyl-2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-7-yloxy)phenyl)urea

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Reaction Conditions

Reaction Steps

3-Tert-butyl-1-phenyl-1H-pyrazol-5-amine (550 mg, 1.8 mmol) was dissolved in CH2Cl2 (25 mL) and an equal volume of saturated NaHCO3 (aq) was added. The biphasic mixture was stirred and cooled to 0° C. with an ice/water bath. After 10 minutes, 2 equiv. of a 1.9 M solution of phosgene in toluene were added. The mixture was vigorously stirred for 10 minutes, the organic layer was isolated, washed with H2O, dried (MgSO4) and concentrated to about 5 mL. This solution was added to a solution of the 7-(4-amino-3-fluorophenoxy)-1-N-methyl-1H-imidazo[4,5-b]pyridin-2(3H)-one (8a) (200 mg, 1.4 mmol) in THF. The solution was stirred for 15 hours at room temperature, the solvents were evaporated and the solid residue was washed with Et2O and CH2Cl2 to afford the title compound as a white solid.

Provenance & Evidence