反应详情

Nitric acid (95%, 42 g, 0.62 mol) was added dropwise (internal temperature kept below 5° C.) to a solution of methyl 3-hydroxy-4-methoxybenzoate (96.5%, 100 g, 0.53 mol) and acetic acid (250 mL) at 0° C. After 10 min at 0° C., a large amount of precipitate had formed and was collected by filtration. The filter cake was washed with water (100 mL×2), and then the crude product was recrystallized from methanol (40 mL) to give 33 g of methyl 3-hydroxy-4-methoxy-2-nitrobenzoate as a light yellow solid. 1H NMR (400 MHz, DMSO-d6): δ 10.64 (s, 1H), 7.49 (d, 1H), 7.22 (d, 1H), 3.93 (s, 3H), 3.76 (s, 3H); MS (ESI): 227.9.

1. customa large amount of precipitate had formed
2. filtrationwas collected by filtration
3. washThe filter cake was washed with water (100 mL×2)
4. customthe crude product was recrystallized from methanol (40 mL)