反应详情

To a solution of 5-bromo-2-chloro-4-(methoxycarbonyl)benzoic acid (1.21 g, 4.15 mmol) in dry dichloromethane (22.5 mL) was added dropwise oxalyl chloride (0.43 mL, 4.96 mmol) followed by N,N-dimethylformamide (1 mL). After being stirred for 2 h at room temperature, the reaction mixture was evaporated and the residue was dissolved in dry dichloromethane (20 mL) at room temperature under agron. After cooling to −5° C., ethylbenzene (0.46 g, 4.35 mmol) was added. Then AlCl3 (1.72 g, 12.8 mmol) was added portionwise and the reaction temperature was kept between −5° C. and 0° C. After being stirred at the same temperature for two hours, the reaction mixture was poured onto ice water and extracted with dichloromethane (100 mL). The combined organic layers were washed with 1 M HCl (60 mL), water (30 mL) and brine (60 mL), dried over anhydrous Na2SO4. Concentration under reduced pressure provided the title compound as a yellow solid. Yield: 1.37 g (87%). 1H NMR (CDCl3, 300 MHz): δ 7.89 (s, 1H), 7.72 (d, J=2.0 Hz, 1H), 7.70 (d, J=2.0 Hz, 1H), 7.64 (s, 1H), 7.33 (s, 1H), 7.30 (s, 1H), 3.98 (s, 3H), 2.70 (q, J=7.8 Hz, 2H), 1.27 (t, J=7.8 Hz, 3H).

1. customthe reaction mixture was evaporated
2. dissolutionthe residue was dissolved in dry dichloromethane (20 mL) at room temperature under agron
3. temperatureAfter cooling to −5° C.
4. customwas kept between −5° C. and 0° C
5. stirringAfter being stirred at the same temperature for two hours
6. additionthe reaction mixture was poured onto ice water
7. extractionextracted with dichloromethane (100 mL)
8. washThe combined organic layers were washed with 1 M HCl (60 mL), water (30 mL) and brine (60 mL)
9. dry with materialdried over anhydrous Na2SO4
10. concentrationConcentration under reduced pressure