The general procedure for the synthesis of 6-chloro-5-methyl-3-nitropyridin-2-amine from 2,6-dichloro-3-methyl-5-nitropyridine is as follows:
A mixture of 2,6-dichloro-3-methyl-5-nitropyridine (10.41 g, 50.3 mmol), 28% aqueous ammonia solution (17 mL, 0.25 mol), potassium carbonate (10.4 g, 75.5 mmol), and tert-butanol (167 mL) was stirred at 60 °C overnight under nitrogen protection. Subsequently, the reaction mixture was continued to be stirred at room temperature for 3 hours. Upon completion of the reaction, the precipitate was collected by filtration and washed three times with distilled water to afford 6-chloro-5-methyl-3-nitropyridin-2-amine (4.25 g, 22.7 mmol, 45% yield) as a yellow solid.
Product characterization data: 1H NMR (400 MHz, DMSO-d6) δ ppm: 2.23 (3H, s), 8.04 (2H, br s), 8.39 (1H, s).
