反应详情

4-Methylpyridazino[4,5-b]indolizin-1-one (5.08 g, 25.5 mmol) was hydrogenated at room temperature and 55 psi using a Parr apparatus in a mixture containing 100 mL each of water, ethanol and acetic acid, 3 mL of concentrated sulfuric acid, and 10% Pd on charcoal (500 mg). A white precipitate was observed. The precipitate and catalyst were filtered through Solka Floc and the solids were washed with methanol and methylene chloride. The washes were evaporated to give 6,7,8,9-tetrahydro-4-(methyl)pyridazino[4,5-b]indolizin-1-one (XI). The reduction filtrate was evaporated in vacuo to remove most of the volatiles, then filtered to isolate additional XI. The aqueous phase was then washed with methylene chloride to extract the remaining XI. The product from all three fractions was combined and dried in vacuo to give 3.2 g (67%) of XI.

1. customwas hydrogenated at room temperature
2. filtrationThe precipitate and catalyst were filtered through Solka Floc
3. washthe solids were washed with methanol and methylene chloride
4. customThe washes were evaporated