4-Methyl-2-nitroaniline (131.2 g, 862 mmol) was used as a raw material and suspended in glacial acetic acid (1.25 L). Bromine (54 mL, 1.05 mol) was added slowly over 1 h at ambient temperature. After addition, the reaction mixture was continued to be stirred for 1 hour. Subsequently, the reaction solution was poured into water (7.5 L) and the suspension was stirred for 30 minutes. The solid product was collected by filtration, washed thoroughly with water (5 x 1 L) and dried to give 2-bromo-4-methyl-6-nitroaniline (187.2 g, 94%) as an orange solid. Its 1H NMR (CDCl3) data were as follows: δ 7.94 (1H, s), 7.56 (1H, s), 6.47 (2H, br s), 2.27 (3H, s).
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