Reaktion #1605780

Reaktionsgleichung

2-bromo-5-methylpyridine

acetonitrile

n-butyl lithium

→

2-(5-methylpyridin-2-yl) acetonitrile

Ausbeute 80.7%

Lösungsmittel

THF

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.WAITThe reaction mixture was kept at minus 78° C. for 1 hour
2. 2
   Temperaturwarmed up slowly to room temperature
3. 3
   workup.STIRRINGstirred for another hour
4. 4
   Sonstigethe layer was separated
5. 5
   WaschenThe organic layer was washed with water and brine
6. 6
   Trocknendried over MgSO4
7. 7
   Filtrationfiltered
8. 8
   Sonstigeevaporated
9. 9
   Sonstigeto give 18 g of crude product
10. 10
    SonstigeThe crude product was purified by silica-gel column chromatography (eluent, PE/EtOAc=15:1)

Vorschrift

To a solution of anhydrous acetonitrile (10.1 mL, 191.83 mmol, 3.3 equiv.) in dry THF (500 mL) was added dropwise n-butyl lithium (2.5 M in hexane, 69.8 mL, 174.39 mmol, 3 equiv.) at minus 78° C. under nitrogen atmosphere. The resulting white suspension was stirred at minus 78° C. for 1 hour, and then a solution of 2-bromo-5-methylpyridine (10.0 g, 58.13 mmol, 1 equiv.) in dry THF (30 mL) was added. The reaction mixture was kept at minus 78° C. for 1 hour and then warmed up slowly to room temperature and stirred for another hour. Ice water was added and the layer was separated. The organic layer was washed with water and brine, dried over MgSO4, filtered, and evaporated to give 18 g of crude product. The crude product was purified by silica-gel column chromatography (eluent, PE/EtOAc=15:1) to give 2-(5-methylpyridin-2-yl) acetonitrile (6.2 g, yield 80%). 1H NMR (300 MHz, CDCl3): δ 8.40 (d, J=3.0 Hz, 1H), 7.54 (dd, J1=3.0 Hz, J2=6.0 Hz, 1 H), 7.32 (d, J=6.0 Hz, 1 H), 3.90 (s, 2H), 2.40 (s, 3H).

Quelle