反应详情

After dissolving at room temperature 2-chloro-5-trifluoromethylbenzoic acid (2.25 g; 10 mmol) in fuming sulfuric acid comprising 20% oleum (6 ml), fuming nitric acid (1.7 ml) is added dropwise over 30 minutes, so as to maintain the temperature of the reaction medium below 60° C. After cooling, ice is added and the precipitate is separated out, washed with water and dried. After recrystallisation from water, 2.15 g of solid corresponding to 2-chloro-3-nitro-5-trifluoromethylbenzoic acid are obtained (m.p.=173° C.).

1. additionis added dropwise over 30 minutes
2. temperatureso as to maintain the temperature of the reaction medium below 60° C
3. temperatureAfter cooling
4. additionice is added
5. customthe precipitate is separated out
6. washwashed with water
7. customdried
8. customAfter recrystallisation from water, 2.15 g of solid corresponding to 2-chloro-3-nitro-5-trifluoromethylbenzoic acid
9. customare obtained (m.p.=173° C.)