反应详情

温度

15 °C

A solution of sodium nitrite (220 mg, 3.18 mmol) in concentrated sulphuric acid (2 ml) was added over 15 minutes to a suspension of 4-amino-2,6-difluorobenzoic acid (550 mg, 3.18 mmol) in acetic acid (6 ml) at 15° C. The mixture was stirred at 15° C. for 1 hour then heated to 90° C. and poured into a solution of copper(I)chloride (800 mg) in concentrated hydrochloric acid (11 ml) at 95° C. The mixture was heated at 95° C. for 45 minutes and then allowed to cool. The mixture was diluted with water, extracted with ethyl acetate, the organic extracts dried (MgSO4) and the solvent removed by evaporation to give 4-chloro-2,6-difluorobenzoic acid (600 mg, 98%)

1. temperaturethen heated to 90° C.
2. temperatureThe mixture was heated at 95° C. for 45 minutes
3. temperatureto cool
4. extractionextracted with ethyl acetate
5. dry with materialthe organic extracts dried (MgSO4)
6. customthe solvent removed by evaporation