反应详情

To a solution of 1,4-difluoro-2-nitrobenzene (14.3 g, 90 mmol) in tetrahydrofuran (250 mL) was added methyl 3-amino-2-methylpropanoate (10.5 g, 90 mmol) and potassium carbonate (24.8 g, 180 mmol). The reaction mixture was heated to reflux and stirred for 15 hours. Then the mixture was concentrated in vacuo, and the residue was dissolved in water (250 mL), extracted with ethyl acetate (100 mL*3). The combined organic layers was separated, dried over anhydrous sodium sulfate, and concentrated to give a residue. The residue was purified by column chromatography (silica gel, petroleum ether/ethyl acetate=5:1) to afford methyl 3-(4-fluoro-2-nitrophenylamino)-2-methylpropanoate as a red solid (14.0 g, 61%).

1. temperatureThe reaction mixture was heated
2. temperatureto reflux
3. concentrationThen the mixture was concentrated in vacuo
4. dissolutionthe residue was dissolved in water (250 mL)
5. extractionextracted with ethyl acetate (100 mL*3)
6. customThe combined organic layers was separated
7. dry with materialdried over anhydrous sodium sulfate
8. concentrationconcentrated
9. customto give a residue
10. customThe residue was purified by column chromatography (silica gel, petroleum ether/ethyl acetate=5:1)