反应详情

4.2 g (15 millimoles) of 6-[p-(3-formylpyrrol-1-yl)-phenyl]4, 5-dihydro-5-methylpyridazin-3-one (compound from Example 1A) in 30 ml of methanol were stirred with 3.36 g (30 millimoles) of 40% strength aqueous dimethylamine solution, 1.8 g (30 millimoles) of acetic acid and 0.75 g (12 millimoles) of sodium cyanoborohydride for 5 hours at room temperature (conversion monitored by thin layer chromatography using SiO2 and 5:2:2 ethyl acetate/acetic acid/water). 50 ml of H2O were added, the mixture was rendered alkaline with 2N NaOH and extracted with ethyl acetate, the organic phase was washed with water, dried with Na2SO4 and purified over a silica gel column using a 4:1 methylene chloride/methanol mixture, and the crystalline residue from the product-containing fractions was recrystallized from ethyl acetate/petroleum ether. 1.4 g of 6-[p-(3-dimethylaminomethylpyrrol-1-yl)-phenyl]-4, 5-dihydro-5-methylpyridazin-3-one of melting point 167°-168° C. were obtained.

1. extractionextracted with ethyl acetate
2. washthe organic phase was washed with water
3. dry with materialdried with Na2SO4
4. custompurified over a silica gel column
5. customthe crystalline residue from the product-containing fractions was recrystallized from ethyl acetate/petroleum ether