反应详情

Sodium hydride (60% w/v dispersion in mineral oil; 1.8 g) was added in portions over 20 minutes to n-butanol (100 ml) with stirring. The mixture was then stirred until no further hydrogen evolution was noted. 2,5-Dibromopyridine (7.1 g) was added and the resulting mixture stirred at reflux for 6 hours. After cooling, the n-butanal was removed by evaporation and the residue was treated with water (50 ml) and extracted with dichloromethane (2×20 ml). The organic extracts were combined, washed with water (20 ml), dried (MgSO4) and evaporated to give 5-bromo-2-n-butoxypyridine (6.3) as a pale yellow oil, NMR (DHSOd6): 0.9-0.96(3H, t), 1.32-1.5(2H, m), 1.62-1.76(2H, m), 4.2-4.28(2H, t), 6.79-6.82(1H, d), 7.85-7.9(1H, d of d) and 8.26(1H, d).

1. stirringthe resulting mixture stirred
2. temperatureat reflux for 6 hours
3. temperatureAfter cooling
4. customthe n-butanal was removed by evaporation
5. additionthe residue was treated with water (50 ml)
6. extractionextracted with dichloromethane (2×20 ml)
7. washwashed with water (20 ml)
8. dry with materialdried (MgSO4)
9. customevaporated