286947-03-3

Step 3: Synthesis of 5-bromo-2-chloro-3-methoxypyridine 5-Bromo-2-chloro-3-hydroxypyridine (1.88 g, 9 mmol), iodomethane (1.42 g, 10 mmol) and potassium carbonate (K2CO3, 2.76 g, 20 mmol) were dissolved in acetonitrile. The reaction mixture was stirred at 80 °C for 4 hours. After completion of the reaction, the solvent was removed by evaporation and the residue was dissolved in dichloromethane (CH2Cl2). The resulting solution was washed with water and the organic phase was dried over anhydrous sodium sulfate and concentrated. Finally, the target product 5-bromo-2-chloro-3-methoxypyridine (1.62 g, 81% yield) was purified by silica gel column chromatography. Mass spectrum (ESI) m/z: 223.9 [M + 1].

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