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一般情况下，在芳环上有游离的存在时，由于许多硝化试剂具有较强的氧化性使得在硝化的同时，氨基也会被氧化成一系列复杂的副产物，有文献报道2,3,5,6-四溴-4--4-硝基-环己-2,5-二烯酮是一种基本上没有氧化性的温和的硝化试剂，可用于带有游离氨基的芳香的硝化。

实例（Lemaire. M, Tetrahedron, 1987, 43 (5), 835.）

A solution containing 2.1 mL of nitric (d=1.52) in 10 mL of acetic acid were added over 10 min to a solution of 2,3,5,6-Tetrabromo-4-methyl-phenol (4.23 g, 10 mmol) in pure acetic acid (30 mL) at 10oC. The suspension was allowed to react for 2 h at 5 oC and precipitated by added 30 mL of water. The crystallized solid were filtered and washed with water and heptane, dried under vacuum to give the product (4.21 g, 90%).

2,3,5,6-Tetrabromo-4-methyl-4-nitro-2,5-cyclohexadien-1-one (2.34 g, 5 mmol) was added to the solution of 2-Bromo-4-fluoro-phenylamine (0.95 g, 5mmol) in dry THF (40 mL). The mixture was stirred for 2 h at room temperature. The solvent was removed under reduced pressure and the residue was purified by column chromatography to give the desired product (0.82 g, 70%).

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