تفاعل #6321

معادلة التفاعل

2-chloroquinoline

diisopropylamine

n-BuLi

dimethylformamide

→

2-chloro-3-quinolinecarboxaldehyde

المردود 92.2%

المذيبات

THF

ظروف التفاعل

المعالجة

1. 1
   workup.STIRRINGthe reaction mixture was stirred an additional 30 min at this temperature
2. 2
   أخرىAfter quenching at -78° C. with glacial acetic acid (1 mL)
3. 3
   درجة الحرارةthe mixture was warmed to room temperature
4. 4
   workup.ADDITIONdiluted with ether (30 mL)
5. 5
   غسيلThe organic phase was washed with saturated NaHCO3 solution (10 mL) and brine (10 mL)
6. 6
   تجفيفwas dried over MgSO4
7. 7
   تركيزConcentration

الإجراء التجريبي

To a solution of 0.46 mL (3.30 mmol) of diisopropylamine in 8 mL of THF at 0.C was added 1.53 mL (3.30 mmol) of n-BuLi dropwise. After 20 min the solution was cooled to -78° C. and 2-chloroquinoline (491 mg, 3.0 mmol) was added neat. The mixture was stirred at -78° C. for 30 min, then dimethylformamide (0.39 mL, 5.04 mmol) was added dropwise and the reaction mixture was stirred an additional 30 min at this temperature. After quenching at -78° C. with glacial acetic acid (1 mL), the mixture was warmed to room temperature and diluted with ether (30 mL). The organic phase was washed with saturated NaHCO3 solution (10 mL) and brine (10 mL), and was dried over MgSO4. Concentration afforded 2-chloro-3-quinolinecarboxaldehyde (530 mg, 92%) as a light yellow solid (mp 145°-149° C.), which was used directly in the next step without further purification. Recrystallization from ethyl acetate afforded the pure compound as light yellow needles: mp (mp 148°-149° C. reported in Meth-Cohn, O.; Narhe, B.; Tarnowski, B. J. Chem. Soc. Perkin Trans. I 1981, 1520.). 1H NMR (300 MHz, CDCl3)δ10.57 (s, 1H), 8.77 (s, 1H), 8.08 (d, 1H, J =9 Hz), 8.0 (d, IH, J =9 Hz), 7.90 (t, 1H, J =9 Hz), 7.67 (t, 1H, J =9 Hz); IR (nujol) 1685, 1575, 1045, 760, 745 cm-1.

المصدر