反应详情

Concentrated sulfuric acid (50 mL) was added slowly to a solution of 2-(4-nitro-3-(2,2,2-trifluoro-ethoxy)phenyl)acetic acid (180 g, 0.64 mol) in MeOH (500 mL). The reaction mixture was stirred at room temperature overnight. The methanol was evaporated and EtOAc (500 mL) was added. The solution was washed with water (2×200 mL) and brine and dried over MgSO4. The solvent was evaporated, the solid residue was stirred with heptane (200 mL), and the solid was filtered. Yield 182.2 g (96%). 1H NMR (300 MHz, CDCl3/TMS): δ 7.82 (d, J=8.7 Hz, 1H), 7.07-7.05 (m, 2H), 4.47 (q, J=8.0 Hz, 2H), 3.68 (s, 3H), 3.67 (s, 2H). 13C NMR (75 MHz, CDCl3/TMS): δ 170.1, 150.4, 141.2, 139.4, 125.9, 123.9, 122.6 (d, 1JCF=277.6 Hz), 117.5, 67.6 (q, 1JCF=36.7 Hz), 52.4, 41.0.

1. customThe methanol was evaporated
2. additionEtOAc (500 mL) was added
3. washThe solution was washed with water (2×200 mL) and brine
4. dry with materialdried over MgSO4
5. customThe solvent was evaporated
6. stirringthe solid residue was stirred with heptane (200 mL)
7. filtrationthe solid was filtered