反应详情

To a solution (150 ml) of ethyl 6-amino-5-nitronicotinate (5.0 g) and 6N aqueous calcium chloride solution (50 ml) in ethanol was added zinc powder (77 g) with heating under reflux. The reaction mixture was heated under reflux for 2 hr, and the zinc powder was removed by filtration. The filtrate was concentrated, diluted with water and extracted with ethyl acetate. The extract was washed with water, dried over magnesium sulfate and concentrated to give the title compound (3.85 g, yield 89%) as pale-brown crystals. 1H NMR (DMSO-d6) δ: 1.37 (3H, t, J=7.0 Hz), 4.38 (2H, q, J=7.1 Hz), 4.95 (2H, s), 6.28 (2H, s), 7.15 (1H, d, J=2.1 Hz), 7.94 (1H, d, J=2.1 Hz).

1. temperaturewith heating
2. temperatureunder reflux
3. temperatureThe reaction mixture was heated
4. temperatureunder reflux for 2 hr
5. customthe zinc powder was removed by filtration
6. concentrationThe filtrate was concentrated
7. additiondiluted with water
8. extractionextracted with ethyl acetate
9. washThe extract was washed with water
10. dry with materialdried over magnesium sulfate
11. concentrationconcentrated