反应详情

To a solution of diisopropylamine (0.97 g, 9.6 mmol) in THF (20 mL) at room temperature was added n-butyl lithium (2.5 N in hexane, 4 mL, 10 mmol) and the resulting solution was stirred at room temperature for 15 minutes. To above solution was added a solution of 3-bromophenylacetic acid (1.0 g, 4.6 mmol) in THF (10 mL) dropwise at room temperature and the stirring was continued for another 15 minutes. Methyl iodide (1.49 g, 10.5 mmol) was added and the resulting mixture was stirred at room temperature for 15 minutes. Satuated sodium chloride (30 mL) was added and the aqueous phase was adjusted to pH 5 by addition of hydrochloric acid (1 N). The resulting mixture was extracted with ethyl acetate (20 mL×3) and the combined organic extracts were dried over sodium sulfate, filtered, and concentrated. The residue was purified by flash chromatography on silica gel using a gradient of formic acid and methanol in dichloromethane to afford 2-(3-bromo-phenyl)-propionic acid (890 mg, 84%) as a white solid. MS: m/z 229 (M+H+).

1. waitthe stirring was continued for another 15 minutes
2. stirringthe resulting mixture was stirred at room temperature for 15 minutes
3. extractionThe resulting mixture was extracted with ethyl acetate (20 mL×3)
4. dry with materialthe combined organic extracts were dried over sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated
7. customThe residue was purified by flash chromatography on silica gel using a gradient of formic acid and methanol in dichloromethane