反应详情

To a stirred solution of tert-butyl 4-fluoropyridin-2-ylcarbamate (1 g, 4.72 mmol) in THF (20 mL) was added dropwise n-BuLi (4.7 mL, 11.8 mmol) at −78° C. After stirring for 0.5 h, a solution of DMF (2 mL) in THF (2 mL) was added dropwise at −78° C. TLC indicated the reaction was completed. The reaction was quenched with 1N HCl at −78° C. to pH=4. Then water (20 mL) was added and extracted with ethyl acetate (3×20 mL). The combined organic phase was washed with brine, dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue was purified by column chromatography (EtOAc:PE=1:2) to give the title compound (0.65 g, 57%) as a white solid. 1H-NMR (600 MHz, DMSO-d6) δ 10.35 (s, 1H), 9.99 (s, 1H), 8.58-8.56 (m, 1H), 7.23-7.21 (m, 1H), 1.46 (s, 9H) ppm.

1. customThe reaction was quenched with 1N HCl at −78° C. to pH=4
2. additionThen water (20 mL) was added
3. extractionextracted with ethyl acetate (3×20 mL)
4. washThe combined organic phase was washed with brine
5. dry with materialdried over anhydrous sodium sulfate
6. concentrationconcentrated under reduced pressure
7. customThe residue was purified by column chromatography (EtOAc:PE=1:2)