تفاعل #1605780

معادلة التفاعل

2-bromo-5-methylpyridine

acetonitrile

n-butyl lithium

→

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

المردود 80.7%

المذيبات

THF

THF

ظروف التفاعل

المعالجة

1. 1
   workup.WAITThe reaction mixture was kept at minus 78° C. for 1 hour
2. 2
   درجة الحرارةwarmed up slowly to room temperature
3. 3
   workup.STIRRINGstirred for another hour
4. 4
   أخرىthe layer was separated
5. 5
   غسيلThe organic layer was washed with water and brine
6. 6
   تجفيفdried over MgSO4
7. 7
   ترشيحfiltered
8. 8
   أخرىevaporated
9. 9
   أخرىto give 18 g of crude product
10. 10
    أخرىThe crude product was purified by silica-gel column chromatography (eluent, PE/EtOAc=15:1)

الإجراء التجريبي

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).

المصدر