反应详情

温度

120 °C

To N-isobutyl-2-piperidone (1.13 g) was added an aqueous methanesulfonic acid solution (2.8 g/3.8 ml), and the mixture was refluxed at 120° C. for 2 days. The mixture was returned to room temperature, and sodium carbonate (1.55 g) was slowly added thereto. Then, the resulting solution was added dropwise to a suspension of 5-bromo-2-chloronicotinaldehyde (1.0 g) and sodium carbonate (1.25 g) in DMSO (10 ml) at 90° C. After stirring as it is for 2 hours, the mixture was cooled to 0° C. and water was added thereto. Then, 1 N hydrochloric acid (20 ml) was added and the mixture was extracted with ethyl acetate. The organic layer was washed with saturated brine, and dried over magnesium sulfate. The solvent was distilled off under reduced pressure and the residue as it is was dissolved in DMF (20 ml). Then, potassium carbonate (1.25 g) and iodomethane (0.57 ml) were added thereto, and the mixture was stirred at room temperature under a nitrogen atmosphere for 2 hours. Water was added thereto and the mixture was extracted with ethyl acetate. The organic layer was washed with saturated brine, and dried over magnesium sulfate. The solvent was distilled off under reduced pressure, and then the resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate=10:1→hexane:ethyl acetate=4:1) to give methyl 5-[(5-bromo-3-formylpyridin-2-yl)(isobutyl)amino]pentanoate (867 mg) as a yellow oily material.

1. customwas returned to room temperature
2. temperaturethe mixture was cooled to 0° C.
3. extractionthe mixture was extracted with ethyl acetate
4. washThe organic layer was washed with saturated brine
5. dry with materialdried over magnesium sulfate
6. distillationThe solvent was distilled off under reduced pressure
7. dissolutionthe residue as it is was dissolved in DMF (20 ml)
8. additionThen, potassium carbonate (1.25 g) and iodomethane (0.57 ml) were added
9. stirringthe mixture was stirred at room temperature under a nitrogen atmosphere for 2 hours
10. additionWater was added
11. extractionthe mixture was extracted with ethyl acetate
12. washThe organic layer was washed with saturated brine
13. dry with materialdried over magnesium sulfate
14. distillationThe solvent was distilled off under reduced pressure
15. customthe resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate=10:1→hexane:ethyl acetate=4:1)