Hydrochloric Acid → 3-Benzyl-2-(3-cyclopropoxy-4-difluoromethoxyphenyl)-1,5-dihydropyrrolo[2,3-d]pyridazin-4-one

Participants

Reaction Steps

To 20 ml of ethanol solution containing 198 mg (0.364 mmol) of 3-benzyl-1-benzyloxymethyl-2-(3-cyclopropoxy-4-difluoromethoxyphenyl)-1,5-dihydropyrrolo[2,3-d]pyridazin-4-one obtained in Example 19-(b), then, 28 mg of 5% palladium-active carbon and 0.36 ml of 1N hydrochloric acid were added thereto, and the mixture was stirred under 1 atm hydrogen atmosphere at 50° C. for 3.8 hours. After completion of the reaction, the reaction mixture was filtered, the filtrate was concentrated under reduced pressure, 8.6 ml of methanol and 4.3 ml of 28% aqueous ammonia were added to the obtained solid and the mixture was stirred at room temperature for 1 hour. Then, the solution was concentrated under reduced pressure, water was added to the obtained concentrate, and the precipitated solid was collected by filtration. The obtained solid was washed successively with water and then with diisopropyl ether and dried under reduced pressure to obtain 128 mg of the title compound as a white solid. (Yield: 84%)

Provenance & Evidence