反应详情

4-Bromo-3-fluorobenzoic acid (4.38 g) was dissolve in tetrahydrofuran (50 mL), 1-ethyl-3-(3′-dimethylaminopropyl)carbodiimide hydrochloride (4.6 g), 1-hydroxybenzotriazole 1hydrate (3.24 g) and piperazine-1-carboxylic acid tert-butyl ester (4.47 g) were added, and the mixture was stirred at room temperature. The reaction mixture was poured into water under cooling, 4N aqueous sodium hydroxide solution and ethyl acetate were added and the mixture was extracted with ethyl acetate. The organic layer was washed with 4N aqueous sodium hydroxide solution and saturated brine, then washed with saturated brine, and dried over sodium sulfate. The solvent was evaporated under reduced pressure. The residue was purified by column chromatography (ethyl acetate:hexane) to give the title compound (7.01 g).

1. temperatureunder cooling
2. extractionthe mixture was extracted with ethyl acetate
3. washThe organic layer was washed with 4N aqueous sodium hydroxide solution and saturated brine
4. washwashed with saturated brine
5. dry with materialdried over sodium sulfate
6. customThe solvent was evaporated under reduced pressure
7. customThe residue was purified by column chromatography (ethyl acetate:hexane)