878207-92-2

878207-91-1

878207-92-2

2-(Methoxycarbonyl)-3-methylpyridin-1-en-1-ol salt (500 mg, 2.99 mmol, 1.00 eq.) was used as a starting material and dissolved in phosphoryl chloride (2 mL). The reaction mixture was stirred at 110 °C for 4 hours. Upon completion of the reaction, the reaction was quenched with ice water and the pH was adjusted to 7. Subsequently, the aqueous phase was extracted with ethyl acetate (3 × 10 mL). The organic layers were combined, dried with anhydrous sodium sulfate, and concentrated under reduced pressure to remove the solvent. The crude product was purified by silica gel column chromatography with ethyl acetate/petroleum ether (1:5, v/v) as eluent to afford methyl 6-chloro-3-methylpyridine-2-carboxylate (230 mg, 41% yield) as a white solid.LC-MS (ESI, m/z): 186 [M + H]+.