反应详情

温度

-78 °C

To a solution of 2-benzyloxy-5-bromopyridine described in Manufacturing Example 231-1-1 (53.0 g, 201 mmol) in diethyl ether (500 mL) was added n-butyl lithium (82.8 mL, 2.67 M n-hexane solution, 221 mmol) was added dropwise on a dry ice-ethanol bath (−78° C.) under nitrogen atmosphere, which was stirred for 30 minutes at −78° C. While cooling at the same temperature, N,N-dimethylformamide (17.6 g, 241 mmol) was added to this reaction mixture, which was stirred for 30 minutes. Water and ethyl acetate were added to the reaction mixture, which was stirred for 10 minutes at room temperature, the organic layer was then separated. The organic layer was washed with water and saturated aqueous sodium chloride, dried over anhydrous magnesium sulfate, and then filtered. The filtrate was concentrated under a reduced pressure. The residue was purified by NH silica gel column chromatography (ethyl acetate:heptane=1:5 then 1:4) to obtain the title compound (36.8 g, 86%).

1. additionwas added dropwise on a dry ice-ethanol bath (−78° C.) under nitrogen atmosphere
2. additionwas added to this reaction mixture, which
3. stirringwas stirred for 30 minutes
4. stirringwas stirred for 10 minutes at room temperature
5. customthe organic layer was then separated
6. washThe organic layer was washed with water and saturated aqueous sodium chloride
7. dry with materialdried over anhydrous magnesium sulfate
8. filtrationfiltered
9. concentrationThe filtrate was concentrated under a reduced pressure
10. customThe residue was purified by NH silica gel column chromatography (ethyl acetate