反应详情

27 g of 2-chloro-3-nitro-5-trifluoromethyl-benzoic acid and 1 g of tetraethylammonium chloride are initially introduced into 200 ml of methanol, and 70 g of 50% strength sodium hydroxide solution are added dropwise, whilst stirring. The mixture is subsequently stirred at 65° C. for 5 hours, diluted with 300 ml of H2O and then rendered acid with hydrochloric acid. The solid product is filtered off and recrystallised from water. 16 g of 2-hydroxy-3-nitro-5-trifluoromethylbenzoic acid with the melting point: 166° to 168° C. are obtained.

1. additionare added dropwise
2. stirringThe mixture is subsequently stirred at 65° C. for 5 hours
3. filtrationThe solid product is filtered off
4. customrecrystallised from water