反应详情

温度

10 °C

2-hydroxy-5-(2,3,5,6-tetrafluoro-4-trifluoromethyl-benzylamino)benzoic acid (10 g, 0.261 mole), as prepared in Example 3, was added to anhydrous ethanol (500 ml) and then the temperature was allowed to rise to 50° C. for complete dissolution. The resulting solution was cooled to 10° C. The pH of the solution was adjusted to 6.8-7.0 using a separately prepared solution of 85%-potassium hydroxide (17.22 g, 0.261 mole) and anhydrous ethanol (30 ml). The reaction mixture was stirred for 2 hours at room temperature and then the precipitated crystals were filtered and dried to give 100.8 g (0.239 mole, 91.7% yield) of potassium 2-hydroxy-5-(2,3,5,6-tetrafluoro-4-trifluoromethyl-benzylamino)benzoate as the desired compound.

1. dissolutionto rise to 50° C. for complete dissolution
2. filtrationthe precipitated crystals were filtered
3. customdried