反应详情

温度

-78 °C

2,2-Dimethyl-N-pyridin-2-yl-propionamide (20.3 g) was dissolved in tetrahydrofuran (230 ml) to prepare a solution which was then cooled to −78° C. A 2.44 M n-butyllithium/n-hexane solution (100 ml) was gradually added dropwise thereto, and the mixture was stirred at −78° C. for 15 min. The reaction solution was stirred at 0° C. for 2 hr and was then again cooled to −78° C. A solution of N,N-dimethylformamide (25.0 g) in tetrahydrofuran (25 ml) was gradually added dropwise thereto. The temperature of the mixture was raised to room temperature. The reaction solution was then poured into a mixture of ice (50 g) and 6 N hydrochloric acid (150 ml), and the mixture was stirred at room temperature for 20 min. The aqueous layer was neutralized with potassium carbonate powder and was extracted with diethyl ether. The diethyl ether layer was then washed with water and saturated brine and was dried over magnesium sulfate. The solvent was removed by distillation under the reduced pressure, and the residue was purified by column chromatography using acetone-chloroform to give N-(3-formyl-pyridin-2-yl)-2,2-dimethyl-propionamide (11.8 g, yield 50%).

1. customto prepare a solution which
2. stirringThe reaction solution was stirred at 0° C. for 2 hr
3. temperaturewas then again cooled to −78° C
4. temperatureThe temperature of the mixture was raised to room temperature
5. stirringthe mixture was stirred at room temperature for 20 min
6. extractionwas extracted with diethyl ether
7. washThe diethyl ether layer was then washed with water and saturated brine
8. dry with materialwas dried over magnesium sulfate
9. customThe solvent was removed by distillation under the reduced pressure
10. customthe residue was purified by column chromatography