反应详情

温度

70 °C

A mixture of 4-(N,N-dimethylsulphamoyl)-2-trifluoromethylbenzamide (1.38 g), acetic acid (10 ml) and concentrated sulphuric acid (0.5 ml) were heated to 70° C. and isoamyl nitrite (15 ml) was added over 4 hours. After cooling the mixture was poured into water and extracted with ethyl acetate and washed with water. The organic phase was extracted with 2 M sodium carbonate and the aqueous layer acidified to pH 1 with 2 M HCl. This was extracted with ethyl acetate, washed with water, dried (anhydrous magnesium sulphate) and filtered. The filtrate was evaporated to dryness and the residue passed through a short silica column eluting with dichloromethane-ethyl acetate to give 4-(N,N-dimethylsulphamoyl)-2-trifluoromethylbenzoic acid (0.98 g) as a white solid, m.p. 188.8°-189.4° C.

1. temperatureAfter cooling the mixture
2. extractionextracted with ethyl acetate
3. washwashed with water
4. extractionThe organic phase was extracted with 2 M sodium carbonate
5. extractionThis was extracted with ethyl acetate
6. washwashed with water
7. dry with materialdried (anhydrous magnesium sulphate)
8. filtrationfiltered
9. customThe filtrate was evaporated to dryness
10. washeluting with dichloromethane-ethyl acetate