反应详情

A mixture of 3-acetyl-1-[2-(difluoromethoxy)phenyl]-5-methoxypyridazin-4(1H)-one (3.70 g, 11.93 mmol) and N,N-dimethylformamide dimethyl acetal (50 mL) was refluxed for 5 h and stirred overnight at room temperature. The precipitate was collected by filtration and washed with AcOEt to give the title compound (4.07 g, 93% yield) as yellow crystals: 1H NMR (300 MHz, CDCl3): δ ppm 2.90 (3H, s), 3.12 (3H, br s), 3.87 (3H, s), 5.87 (1H, br s), 6.31-6.82 (2H, m), 7.30-7.41 (2H, m), 7.43-7.50 (1H, m), 7.63 (1H, dd, J=7.8, 1.8 Hz), 7.74 (1H, s).

1. temperaturewas refluxed for 5 h
2. filtrationThe precipitate was collected by filtration
3. washwashed with AcOEt