反应详情

温度

-78 °C

6-Chloro-4-methylaminonicotinic acid ethyl ester (33 g, 156 mmol) was dissolved in anhydrous THF (500 mL) and cooled to −78° C. To the solution was slowly added a solution of LAH (12.5 g, 330 mmol) in THF (500 mL). After the addition was complete, the reaction was kept at −78° C. for 1 h. The mixture was warmed to rt and a small amount of MeOH/ethyl acetate (1/1) was slowly added to destroy the excess LAH. The crude reaction mixture was filtered through a celite plug, washing twice with ethyl acetate. The filtrate was concentrated, and the crude residue was purified by silica gel chromatography (1:1 hexanes/ethyl acetate eluant). The title compound was obtained as a white solid. 1H NMR (300 MHz, CDCl3) δ 7.36 (s, 1H), 6.48 (s, 1H), 5.55 (bs, 1H), 4.63 (s, 2H), 2.89 (d, J=5.1 Hz, 3H).

1. additionAfter the addition
2. temperatureThe mixture was warmed to rt
3. customto destroy the excess LAH
4. customThe crude reaction mixture
5. filtrationwas filtered through a celite plug
6. washwashing twice with ethyl acetate
7. concentrationThe filtrate was concentrated
8. customthe crude residue was purified by silica gel chromatography (1:1 hexanes/ethyl acetate eluant)