Реакция #1605780

Уравнение реакции

2-bromo-5-methylpyridine

acetonitrile

n-butyl lithium

→

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

Выход 80.7%

Растворители

THF

THF

Условия реакции

Обработка

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

Методика

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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