反应详情

To a stirred solution of 3-bromo-2-fluorobenzoic acid A1 (25.0 g, 114.15 mmol) in ethanol (400 mL) was added conc. H2SO4 (3 mL) at RT and stirred at reflux temperature for 24 h. The reaction was monitored by LC-MS; after completion of the reaction, the reaction mixture was concentrated to obtain the residue. The residue was diluted with EtOAc (500 mL), washed with water (300 mL), brine (300 mL), dried over Na2SO4, filtered and concentrated under reduced pressure to afford compound A2 (26.0 g, 92%) as a light yellow liquid. 1H NMR (400 MHz, CDCl3): δ 7.88-7.84 (m, 1H), 7.72-7.69 (m, 1H), 7.08-7.04 (m, 1H), 4.39 (q, J=7.2 Hz, 2H), 1.39 (t, J=7.2 Hz, 3H).

1. temperatureat reflux temperature for 24 h
2. customafter completion of the reaction
3. concentrationthe reaction mixture was concentrated
4. customto obtain the residue
5. washwashed with water (300 mL), brine (300 mL)
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure