反应详情

A mixture of 3-amino-4-(4'-cyanophenyl)aminopyridine (Preparation 26(b)) (2.00 g, 9.5 mmol) and propionic anhydride (12.2 ml, 95 mmol) were heated together under nitrogen at reflux for 17 hours. The resulting solution was treated with excess aqueous sodium bicarbonate and the product was extracted into dichloromethane (3×150 ml). The combined extracts were dried (MgSO4), concentrated under reduced pressure, and the residue was purified by flash chromatography (gradient elution with ethyl acetate/methanol) to give the title compound as a brown solid (510 mg, 22%).

1. temperaturewere heated together under nitrogen
2. temperatureat reflux for 17 hours
3. extractionthe product was extracted into dichloromethane (3×150 ml)
4. dry with materialThe combined extracts were dried (MgSO4)
5. concentrationconcentrated under reduced pressure
6. customthe residue was purified by flash chromatography (gradient elution with ethyl acetate/methanol)