反応 #1605780

反応方程式

2-bromo-5-methylpyridine

acetonitrile

n-butyl lithium

→

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

収率 80.7%

溶媒

THF

THF

反応条件

後処理

1. 1
   workup.WAITThe reaction mixture was kept at minus 78° C. for 1 hour
2. 2
   温度warmed up slowly to room temperature
3. 3
   workup.STIRRINGstirred for another hour
4. 4
   その他the layer was separated
5. 5
   洗浄The organic layer was washed with water and brine
6. 6
   乾燥dried over MgSO4
7. 7
   ろ過filtered
8. 8
   その他evaporated
9. 9
   その他to give 18 g of crude product
10. 10
    その他The crude product was purified by silica-gel column chromatography (eluent, PE/EtOAc=15:1)

実験手順

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).

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