Potassium Carbonate → tert-Butyl (3-{4-[(cyclobutyloxy)methyl]-2,6-dimethoxyphenyl}-6-methoxypyrazolo[5,1-b][1,3]thiazol-7-yl)carbamate

Participants

Reaction Conditions

Reaction Steps

To a mixture of tert-butyl (3-bromo-6-methoxypyrazolo[5,1-b][1,3]thiazol-7-yl)carbamate (987 mg, 2.83 mmol), DME (80 mL) and water (28 mL) were added {4-[(cyclobutyloxy)methyl]-2,6-dimethoxyphenyl}boronic acid (904 mg, 3.4 mmol), potassium carbonate (785 mg, 5.68 mmol), triphenylphosphine (370 mg, 1.42 mmol) and palladium acetate (63.7 mg, 0.282 mmol) in that order, and the mixture was stirred at 90° C. (internal temperature) for 3 hours. Water was added to the reaction mixture, and then ethyl acetate was added. After thoroughly shaking the mixture, the organic layer was separated and the organic layer was washed with brine and dried over anhydrous magnesium sulfate. The mixture was filtered, and then the solvent in the filtrate was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (mixture of n-heptane and ethyl acetate: n-heptane/ethyl acetate=2/1) to obtain the title compound (1.24 g, 2.53 mmol).

Provenance & Evidence