反应详情

To a solution of ethyl 1H-pyrazole-4-carboxylate (0.98 g, 7.0 mmol) in N,N-dimethylformamide (10 mL) was added 60% sodium hydride (0.42 g, 10.5 mmol) under ice-cooling, and the mixture was stirred at the same temperature for 20 min. Bromoacetonitrile (0.63 mL, 9.10 mmol) was added to the reaction mixture, the ice bath was removed and the mixture was stirred for 4.5 hr. The reaction mixture was diluted with water, extracted with ethyl acetate, washed successively with water and saturated brine, dried over sodium sulfate, and concentrated under reduced pressure. The residue was purified by column chromatography (carrier: silica gel, eluent: hexane-ethyl acetate) to give the title compound (1.14 g, 90%) as a colorless oil.

1. temperaturecooling
2. customthe ice bath was removed
3. stirringthe mixture was stirred for 4.5 hr
4. additionThe reaction mixture was diluted with water
5. extractionextracted with ethyl acetate
6. washwashed successively with water and saturated brine
7. dry with materialdried over sodium sulfate
8. concentrationconcentrated under reduced pressure
9. customThe residue was purified by column chromatography (carrier: silica gel, eluent: hexane-ethyl acetate)