反应详情

To a solution of 2-difluoromethoxy-6-nitro-benzonitrile (4.0 g, 14.9 mmol) (Example I3) in isopropanol (100 ml) is added tin(II) chloride (10.2 g, 53.6 mmol). Aqueous hydrochloric acid (concentrated) (14.4 ml) is added slowly and the reaction mixture is heated to reflux for 30 minutes. The reaction mixture is cooled to room temperature, diluted with water and the pH is adjusted to 10 by addition of NaOH (2M). The mixture is extracted three times with ethyl acetate. The combined organic phases are dried over sodium sulfate and concentrated to yield 2-amino-6-difluoromethoxy-benzonitrile (3.32 g, 93% yield) in pure form. 1H-NMR (CDCl3, 400 MHz): 7.05 (t, 1H), 6.65 (d, 1H), 6.55 (t, 1H), 6.50 (t, 1H), 4.25 (s, br, 2H) ppm.

1. temperaturethe reaction mixture is heated
2. temperatureto reflux for 30 minutes
3. extractionThe mixture is extracted three times with ethyl acetate
4. dry with materialThe combined organic phases are dried over sodium sulfate
5. concentrationconcentrated