反应详情

To a solution of 4-amino-2-((2-chlorophenyl)amino)-3-fluoro-5-hydroxybenzoic acid in trimethyl orthoformate (100 mL) was added p-TsOH (0.42 g, 1.35 mmol). The reaction mixture was stirred for 1 h and treated with water (300 mL). The precipitate was filtered off and the filter cake was washed with water to afford a yellow solid (12.31 g, 87.9% yield for two steps). 1H NMR (400 MHz, DMSO-d6): δ 13.9 (s, 1H), 9.05 (s, 1H), 8.8 (s, 1H), 8.23 (s, 1H), 7.43 (m, 1H), 7.15 (m, 1H), 6.98 (m, 1H), 6.74 (m, 1H).

1. filtrationThe precipitate was filtered off
2. washthe filter cake was washed with water
3. customto afford a yellow solid (12.31 g, 87.9% yield for two steps)