Isopropanol → 2-Bromo-6-isopropoxypyridine
Reaktionsgleichung
[Na].Br[C:3]1[CH:8]=[CH:7][CH:6]=[C:5]([Br:9])[N:4]=1.CCCC(C)C.[CH:16]([OH:19])([CH3:18])[CH3:17]>>[Br:9][C:5]1[CH:6]=[CH:7][CH:8]=[C:3]([O:19][CH:16]([CH3:18])[CH3:17])[N:4]=1Komponenten
5
Reaktionsbedingungen
- Temperatur
- 80 °C
Versuchsvorschrift
Sodium (0.50 g, 21.7 mmol) was dissolved in isopropanol (50 ml) under an atmosphere of nitrogen with warming at 80° C., then allowed to cool to ambient temperature. 2,6-Dibromopyridine (10.0 g, 41.4 mmol) was added and the solution heated to 90° C. After 5 h the cooled reaction mixture was partitioned between diethyl ether (150 ml) and water (100 ml). Diethyl ether extracts were washed with water and saturated brine then dried over magnesium sulphate, filtered and evaporated in vacuo to give a semi-solid. Addition of isohexane, filtration and concentration in vacuo gave a residue that was purified by chromatography on silica gel eluting with dichloromethane to give 2-bromo-6-isopropoxypyridine (2.1 g) as a colourless liquid: δH (400 MHz, CDCl3) 1.33 (6H, d, J 6), 5.28 (1H, quin, J 6), 6.60 (1H, d, J 8), 7.00 (1H, d, J 7), 7.38 (1H, dd, J 7 and 8); m/z (ES+) 214/216 (M++H).