反应详情

tert-Butyl 2-{1-[(benzyloxy)carbonyl]piperidin-4-yl}-3-oxotetrahydropyridazin-1(2H)-carboxylate (0.84 g) obtained in Example 29a} was dissolved in trifluoroacetic acid (1 mL) and dichloromethane (1.5 mL), and the mixture was stirred at room temperature for 2 hours. The reaction mixture was concentrated under reduced pressure, and the residue was made alkaline with an aqueous sodium bicarbonate solution and then extracted with dichloromethane. The extract was dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. The residue was dissolved in ethanol (10 mL), and 10% palladium on carbon (0.1 g) was added, followed by stirring under a hydrogen atmosphere for 15 hours. After the catalyst was removed, the solvent was distilled off under reduced pressure to obtain the title compound (0.40 g, quantitative) as a yellow oil.

1. concentrationThe reaction mixture was concentrated under reduced pressure
2. extractionextracted with dichloromethane
3. dry with materialThe extract was dried over anhydrous sodium sulfate
4. distillationthe solvent was distilled off under reduced pressure
5. dissolutionThe residue was dissolved in ethanol (10 mL)
6. addition10% palladium on carbon (0.1 g) was added
7. customAfter the catalyst was removed
8. distillationthe solvent was distilled off under reduced pressure