反应详情

A suspension of 2-methyl-5-nitrobenzotrifluoride (3.90 g, 19 mmol), N-bromosuccinimide (NBS, 3.56 g, 20 mmol), 2,2′-azobis(2-methylpropionitrile) (AIBN, 94 mg, 0.6 mmol) in CCl4 (40 mL) was refluxed under N2 for 16 h. HPLC indicated ca. 50% conversion. More NBS (10 mmol) and AIBN (0.6 mmol) was added, and the mixture was refluxed for another 14 h. HPLC indicated ca. 80% conversion. The reaction mixture was cooled down, and the solid was filtered off and washed with EtOAc. The combined filtrate was washed with aq. NaHCO3, dried over Na2SO4, filtered, concentrated on rotovap and further dried under vacuum. 1H NMR shows the ratio of desired product to unreacted 2-methyl-5-nitrobenzotrifluoride is 75:25. This material was not purified but used directly in the next step.

1. temperaturewas refluxed under N2 for 16 h
2. temperaturethe mixture was refluxed for another 14 h
3. temperatureThe reaction mixture was cooled down
4. filtrationthe solid was filtered off
5. washwashed with EtOAc
6. washThe combined filtrate was washed with aq. NaHCO3
7. dry with materialdried over Na2SO4
8. filtrationfiltered
9. concentrationconcentrated on rotovap
10. customfurther dried under vacuum
11. customThis material was not purified