反应详情

温度

-50 °C

5-Bromo-2-methoxypyridine (188 g) was added over 30 minutes to a 1.55 molar solution of n-butyllithium in hexane (770 ml) and ether (1200 ml) stirred at -50° C. The suspension was stirred for 1 hour when pyridine-3-carboxaldehyde (112 g) in ether (200 ml) was added over 30 minutes. The solution was stirred for 3.5 hr and then allowed to warm to ambient temperature. Saturated ammonium chloride solution (100 ml) and water (2 L) was added and the solution was concentrated to ca. 2.5 L in vacuo. Chloroform (3 L) was added and the title compound (41.3 g) was collected by filtration. The chloroform layer was separated, dried over magnesium sulphate and the solvent was removed under reduced pressure. The residue was treated with chloroform (200 ml) and filtered to give a second crop of the product (51.01 g). Recrystallisation from isopropanol/ether gave the title compound, m.p. 129°-130° C.

1. additionwas added over 30 minutes
2. stirringThe solution was stirred for 3.5 hr
3. temperatureto warm to ambient temperature
4. concentrationthe solution was concentrated to ca. 2.5 L in vacuo
5. additionChloroform (3 L) was added
6. filtrationthe title compound (41.3 g) was collected by filtration
7. customThe chloroform layer was separated
8. dry with materialdried over magnesium sulphate
9. customthe solvent was removed under reduced pressure
10. additionThe residue was treated with chloroform (200 ml)
11. filtrationfiltered