869357-63-1

General procedure for the synthesis of methyl 5-bromo-2-chloro-1-methyl-6-oxo-1,6-dihydropyridine-3-carboxylate from methyl 2-chloro-1-methyl-6-oxo-1,6-dihydropyridine-3-carboxylate: to methyl 2-chloro-1-methyl-6-oxo-1,6-dihydropyridine-3-carboxylate (0.100 g, 0.496 mmol) in dimethylformamide ( DMF, 5 mL) solution was added N-bromosuccinimide (NBS, 0.177 g, 0.992 mmol). The reaction mixture was stirred at room temperature in a nitrogen (N2) atmosphere for 4 hours. Upon completion of the reaction, the reaction was quenched with saturated sodium bisulfite solution and subsequently diluted and layered with ethyl acetate (EtOAc) and water (H2O). The aqueous layer was back-extracted with ethyl acetate (2×). The organic layers were combined, dried over anhydrous sodium sulfate (Na2SO4) and concentrated under reduced pressure to give a yellow solid product in quantitative yield.

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