反应详情

温度

-78 °C

A 1 M solution of lithiumhexamethyldisilazide in tetrahydrofuran (35 mL) was added to a solution of (5R)-5-[(1,3-benzothiazol-2-ylsulfonyl)methyl]pyrrolidin-2-one obtained in Reference Example 3-12 (5.01 g) in tetrahydrofuran (150 mL) at −78° C. in a nitrogen gas stream, and the mixture was stirred at −78° C. for 40 minutes. A solution of (4-{[tert-butyl(dimethyl)silyl]oxy}phenyl)(5-chloro-6-methoxypyridin-2-yl)methanone obtained in Reference Example 1-28 (3.2 g) in tetrahydrofuran (20 mL) was added, and the mixture was stirred at −78° C. for two hours. The reaction solution was poured into water, followed by extraction with ethyl acetate. The organic layer was washed with brine, dried over anhydrous magnesium sulfate and filtered. The solvent was then evaporated under reduced pressure. The residue was purified by silica gel column chromatography (chloroform:ethyl acetate=7:3→3:7) to give (5R)-5-[(E)-2-(4-{[tert-butyl(dimethyl)silyl]oxy}phenyl)-2-(5-chloro-6-methoxypyridin-2-yl)ethenyl]pyrrolidin-2-one as a colorless oil (688 mg, 17%).

1. additionwas added
2. stirringthe mixture was stirred at −78° C. for two hours
3. extractionfollowed by extraction with ethyl acetate
4. washThe organic layer was washed with brine
5. dry with materialdried over anhydrous magnesium sulfate
6. filtrationfiltered
7. customThe solvent was then evaporated under reduced pressure
8. customThe residue was purified by silica gel column chromatography (chloroform:ethyl acetate=7:3→3:7)