反应详情

温度

-6 °C

To an ice-cooled slurry of NaH (475 mg, 11.8 mmol, 60%) in dry DMF (10 mL) was added CH2(COOEt)2 dropwise under an N2 atmosphere. After 20 minutes, 1,2,4-trifluoro-5-nitrobenzene (1 g, 5.6 mmol) was added dropwise over 10 minutes and the mixture was stirred at −6° C. overnight. After the reaction was completed, the mixture was diluted with water and extracted with EtOAc. The organic layer washed with brine, dried over anhydrous Na2SO4 and concentrated. The residue was purified chromatography to give diethyl (2,5-difluoro-4-nitrophenyl)propanedioate. 1H-NMR (400 MHz, CDCl3) δ ppm 7.87˜7.84 (m, 1H), 7.54˜7.58 (m, 1H), 4.98 (s, 1H), 4.23˜4.27 (m, 4H), 1.28 (t, J=7.0 Hz, 6H).

1. extractionextracted with EtOAc
2. washThe organic layer washed with brine
3. dry with materialdried over anhydrous Na2SO4
4. concentrationconcentrated
5. customThe residue was purified chromatography