反应详情

温度

150 °C

LiCl (10.6 g, 0.252 mol) is suspended in a solution of 2-(5-Methyl -3-nitro-pyridin-2-yl)-malonic acid diethyl ester (50 g, 0.168 mol) in DMSO (100 mL) containing water (12 g, 0.678 mol) and is stirred at 150° C. for 3 h. The reaction mixture is cooled, diluted with water (200 mL), and extracted with ethyl acetate. The combined organic phase are washed successively with saturated aqueous NaHCO3, water, brine, dried over Na2SO4, and concentrated in vacuo. The residue is purified by silica gel chromatography eluting with 20% EtOAc-hexanes to afford (5-Methyl-3-nitro-pyridin-2-yl)-acetic acid ethyl ester as an oil; 1H NMR (300 MHz, CDCl3) δ 1.23 (t, J=9 Hz, 3H), 4.15 (q, J=9 Hz, 2H), 4.25 (s, 2H), 8.2 (s, 1H), 8.58 (s, 1H).

1. temperatureThe reaction mixture is cooled
2. extractionextracted with ethyl acetate
3. washThe combined organic phase are washed successively with saturated aqueous NaHCO3, water, brine
4. dry with materialdried over Na2SO4
5. concentrationconcentrated in vacuo
6. customThe residue is purified by silica gel chromatography
7. washeluting with 20% EtOAc-hexanes