反应详情

1,1'-Carbonyldiimidazole (3.829 g, 23.6 mmol) was added to a suspension of 4-pyridinecarboxylic acid-1-oxide (2.986 g, 21.5 mmol) in dry dimethylformamide (50 ml) and the resulting solution was stirred for 45 minutes and treated with a solution of 4-chlorobenzenamine (3.012 g, 23.6 mmol) in dry dimethylformamide (20 ml). After 18 hours, the solution was evaporated in vacuo to give an oil which slowly solidified. The solid was recrystallised from ethyl acetate-cyclohexane and suspended in saturated aqueous sodium bicarbonate solution. The mixture was stirred vigorously for 20 minutes, filtered, and the crystals washed with water (3×10 ml) and ethanol (3×10 ml) and dried in vacuo to give the title compound as a quarter hydrate (1.614 g), m.p. 247°-249°.

1. waitAfter 18 hours
2. customthe solution was evaporated in vacuo
3. customto give an oil which
4. customThe solid was recrystallised from ethyl acetate-cyclohexane
5. stirringThe mixture was stirred vigorously for 20 minutes
6. filtrationfiltered
7. washthe crystals washed with water (3×10 ml) and ethanol (3×10 ml)
8. customdried in vacuo