反应详情

A mixture of 3-amino-4-[N-(4-cyanophenyl)amino]pyridine (see part (b)) (9.31 g, 44.3 mmol), triethyl orthoacetate (40 ml) and acetic anhydride (30 ml) was heated under reflux for 2 hours under nitrogen, cooled, then concentrated under reduced pressure The brown residue was dissolved in 1M hydrochloric acid and washed with ethyl acetate (200 ml). The aqueous layer was rendered basic with saturated aqueous ammonia and extracted with dichloromethane (3×200 ml). The combined extracts were washed with water, dried (MgSO4) and concentrated to give the title compound (6.5 g), as a brown solid.

1. temperaturewas heated
2. temperatureunder reflux for 2 hours under nitrogen
3. temperaturecooled
4. concentrationconcentrated under reduced pressure The brown residue
5. dissolutionwas dissolved in 1M hydrochloric acid
6. washwashed with ethyl acetate (200 ml)
7. extractionextracted with dichloromethane (3×200 ml)
8. washThe combined extracts were washed with water
9. dry with materialdried (MgSO4)
10. concentrationconcentrated