反应详情

Treat a solution of 2-(4-fluoro-3-nitrophenyl)acetic acid (1.5 g, 7.53 mmol) in propionic anhydride (5.40 mL, 45.2 mmol) with 1-methylimidazole (0.600 mL, 7.53 mmol) and stir at RT overnight. Quench the mixture with H2O, stir for 1 h, extract with EtOAc (2×), wash the combined organics with satd. Na2CO3, then brine, dry the organics over MgSO4, concentrate to dryness and purify via silica gel chromatography (EtOAc/Hex) to afford the title compound (830 mg, 52%). 1H NMR (400 MHz, DMSO-d6): δ 8.00 (dd, J=7.4, 2.2 Hz, 1H), 7.61 (ddd, J=8.6, 4.6, 2.2 Hz, 1H), 7.53 (dd, J=11.4, 8.6 Hz, 1H), 3.95 (s, 2H), 2.56 (q, J=7.3 Hz, 2H), 0.96 (t, J=7.3 Hz, 3H); MS (ESI) m/z: 212.1 (M+H+).

1. customQuench the mixture with H2O
2. stirringstir for 1 h
3. extractionextract with EtOAc (2×)
4. washwash the combined organics with satd
5. dry with materialNa2CO3, then brine, dry the organics over MgSO4
6. concentrationconcentrate to dryness
7. custompurify via silica gel chromatography (EtOAc/Hex)