5-Benzyloxymethyl-3-methyl-1-(2-trimethylsilylethoxymethyl)-1,5-dihydropyrrolo[2,3-d]pyridazin-4-one → 3-Methyl-1-(2-trimethylsilylethoxymethyl)-1,5-dihydropyrrolo[2,3-d]pyridazin-4-one

Participants

Reaction Steps

To 380 ml of ethanol solution containing 25.3 g (65 mmol) of 5-benzyloxymethyl-3-methyl-1-(2-trimethylsilylethoxymethyl)-1,5-dihydropyrrolo[2,3-d]pyridazin-4-one obtained in Reference example 24-(c) was added 25 g of 5% palladium-active carbon, and the mixture was stirred under 1 atm hydrogen atmosphere at room temperature for 2.5 hours. After completion of the reaction, insoluble material was removed from the reaction suspension by filtration, 100 ml of 28% aqueous ammonia was added to the obtained filtrate, and the mixture was stirred at room temperature for 5 hours. Then, the solution was concentrated under reduced pressure, 500 ml of water was added to the obtained concentrate, and precipitated solid was collected by filtration. The obtained solid was washed with water, and dried under reduced pressure to obtain 14.3 g of the title compound as a pale yellowish solid. (Yield: 79%)

Provenance & Evidence