反应详情

温度

43 °C

2,3,6-Trichlorobenzoic acid (20.84 g, 92.4 mmol, prepared by the method of M. T. Goebel, U.S. Pat. No. 3,391,185, E.I. DuPont, Jul. 2, 1968) was stirred at 40°-45° C. in 89.1 mL of concentrated sulfuric acid. A solution containing 23.2 g of concentrated sulfuric acid and 23.2 g of fuming nitric acid was added at a rate so to maintain the temperature between 40°-45° C. An additional 20 mL of concentrated sulfuric acid was added. The reaction mixture was stirred at 43° C. for 1.5 hours and then poured over ice water. The resulting crystals were filtered and recrystallized from toluene-hexane to give 23.40 g (94%) of product; mp 149°-151° C.

1. additionwas added at a rate so
2. temperatureto maintain the temperature between 40°-45° C
3. filtrationThe resulting crystals were filtered
4. customrecrystallized from toluene-hexane