反应详情

3.6 g 2-Chloro-4-fluoro-5-nitrophenol was dissolved in dimethylformamide and treated with potassium carbonate. The mixture was stirred at room temperature for one hour and then 3.3 g 2,2-difluorocyclopropylmethyl bromide added. It was the heated at 80° C. for 2 hours and added to water. The mixture was extracted with methylene chloride and the organic phase washed with saturated brine, dried over magnesium sulphate and concentrated. The residue was chromatographed on silica gel using a mixture of 3 parts hexane and 1 part ethyl acetate. There was obtained 5 g (=93% of theory) of yellow crystals whose nmr spectrum is as follows: δ=1.1-2.4 ppm (m) 3H, δ=4.15 ppm (d 7 Hz,tr 1.5 Hz) 2H, δ=7.35 ppm (d 10 Hz) 1H, δ=7.5 ppm (d 7 Hz) 1H.

1. temperatureheated at 80° C. for 2 hours
2. extractionThe mixture was extracted with methylene chloride
3. washthe organic phase washed with saturated brine
4. dry with materialdried over magnesium sulphate
5. concentrationconcentrated
6. customThe residue was chromatographed on silica gel using
7. additiona mixture of 3 parts hexane and 1 part ethyl acetate
8. customThere was obtained 5 g (=93% of theory) of yellow crystals whose nmr spectrum