反应详情

温度

-20 °C

A solution of intermediate 5 (19.28 g, 90.6 mmol) in THF (181 mL) was treated with n-BuLi (108.8 mL, 272 mmol) and the resulting mixture was stirred at −20° C. for 3 h. After addition of DMF (20.81 mL, 271.86 mmol), the reaction was allowed to warm to rt. The reaction was poured into cold 6N HCl and stirred for 15 min. The mixture was then neutralized with anhydrous K2CO3 to pH=7 and extracted with Et2O. The combined organic layers were washed with water, brine, dried over anhydrous Na2SO4, concentrated in vacuo and purified by recrystallization from EtOAc and hexanes to afford N-(6-chloro-3-formylpyridin-2-yl)pivalamide (intermediate 6) (12.84 g, 59%).

1. temperatureto warm to rt
2. stirringstirred for 15 min
3. extractionextracted with Et2O
4. washThe combined organic layers were washed with water, brine
5. dry with materialdried over anhydrous Na2SO4
6. concentrationconcentrated in vacuo
7. custompurified by recrystallization from EtOAc and hexanes