Hydrogen Bromide → 1-Bromo-5-fluoro-4-methoxy-2-nitrobenzene

Participants

Reaction Conditions

Reaction Steps

5-Fluoro-4-methoxy-2-nitroaniline obtained in Reference Example 14 (4.1 g) was dissolved in a mixed solvent of water (20 ml) and 1,4-dioxane (10 ml), 48% hydrobromic acid (12 ml) was added to the solution under refluxing, and then the mixture was refluxed for 15 minutes. The reaction mixture was cooled to 0° C., sodium nitrite was added dropwise thereto, and the mixture was stirred at 0° C. for 15 minutes. The resulting mixture was added dropwise to a solution of copper (I) bromide (3.6 g) in a mixture of water (20 ml) and 48% hydrobromic acid (12 ml) at 0° C. The mixture was stirred at 60° C. for 15 minutes, cooled to room temperature, and further stirred for 1 hour. The reaction mixture was extracted with ethyl acetate, and the extract was washed with water, dried over magnesium sulfate and concentrated. The residue was purified by column chromatography (developing solvent:ethyl acetate-hexane=1:8) to obtain the title compound as crystals (5 g, 91%).

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