Synthesis
(a) 3,4-Dinitrobenzoic acid (10 g, 47.2 mmol) was dissolved in ethanol (50 mL) and triethylamine (TEA, 13 mL) and methylamine (2M solution in methanol, 35 mL, 70 mmol) were added. The reaction mixture was stirred at room temperature for 24 hours. After completion of the reaction, the mixture was concentrated and water was added to the residue. The mixture was filtered and the filtrate was acidified with acetic acid (AcOH). The precipitated solid was collected and dried to give 4-methylamino-3-nitrobenzoic acid. Yield: 7.5 g (81%).
