反应详情

2,2-dimethyl-N-pyridin-4-yl-propionamide (1.6 g, 8.977 mol) was dissolved in anhydrous tetrahydrofuran (20 ml) under nitrogen atmosphere and then cooled to −780, and then 2.5M solution of n-butyl lithium (n-BuLi) in n-hexane (9 ml, 22.443 mmol) was added thereto dropwise and then stirred at 0□ for 2.5 hours until yellow crystals were formed. After cooling the reaction mixture to −78□, trimethylboron (2.5 ml, 22.443 mmol) was added thereto dropwise for 10 minutes, and the temperature was raised slowly up to □0. After stirring for 2 hours, acetic acid (1.9 ml) and 30% w/w aqueous solution of hydrogen peroxide were added dropwise to the reaction solution at 0□, and then after stirring for 30 minutes, water (1 ml) was added thereto dropwise and then stirred at room temperature for 18 hours. Water was added and the mixture was evaporated under reduced pressure, and the residue was extracted by using water and 10% isopropanol/chloroform. The combined organic layer was treated with active carbon and the filtrate was washed with saturated saline solution, dried over anhydrous sodium sulfate (Na2SO4), filtered and evaporated under reduced pressure. The residue was purified by column chromatography on silica eluting with a solvent of dichloromethane:methanol=20:1. The fractions containing the product were collected and evaporated to obtain white solid (1.16 g, 67%).

1. temperaturecooled to −780
2. customwere formed
3. additionwas added
4. waitdropwise for 10 minutes
5. temperaturethe temperature was raised slowly up to □0
6. stirringAfter stirring for 2 hours
7. stirringafter stirring for 30 minutes
8. stirringdropwise and then stirred at room temperature for 18 hours
9. customthe mixture was evaporated under reduced pressure
10. extractionthe residue was extracted
11. additionThe combined organic layer was treated with active carbon
12. washthe filtrate was washed with saturated saline solution
13. dry with materialdried over anhydrous sodium sulfate (Na2SO4)
14. filtrationfiltered
15. customevaporated under reduced pressure
16. customThe residue was purified by column chromatography on silica eluting with a solvent of dichloromethane
17. additionThe fractions containing the product
18. customwere collected
19. customevaporated