84832-01-9

Step 3: Methyl 2,6-difluorobenzoate (68.8 g, 0.4 mol) was dissolved in methanol. Potassium nitroperoxide (48.5 g, 0.48 mol) was added to concentrated sulfuric acid (300 mL) in three portions under stirring. The reaction mixture was stirred continuously at room temperature for 2 hours. Upon completion of the reaction, the mixture was slowly dripped into ice water (500 mL) and subsequently filtered. The solid product was washed with water and dried to give methyl 2,6-difluoro-3-nitrobenzoate (89 g, 100% yield). The product was characterized by 1H NMR (DMSO-d6): δ 8.49-8.43 (1H, m), 7.56-7.51 (1H, m), 3.95 (3H, s).

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