2-Chloroisonicotinic acid (5.10 g, 32.38 mmol) was dissolved in methanol (150 mL) and thionyl chloride (12 mL) was added slowly. The reaction mixture was stirred at 70 °C for 5 h. After completion of the reaction, the reaction solution was concentrated under reduced pressure by rotary evaporator. The concentrated residue was dissolved in dichloromethane (250 mL), washed sequentially with 10% aqueous potassium carbonate (2×150 mL), dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated by rotary evaporation to afford methyl 2-chloropyridine-4-carboxylate (SLA 07150) as a yellow solid (5.06 g, 91% yield).The molecular weight of SRA 07150 was 171.58; melting point was 33.0 °C; thin layer chromatography (TLC) Rf value was 0.80 (unfolding reagent ratio methanol:dichloromethane=10:90).1H-NMR (CDCl3, δ): 3.98 (s, 3H, CH3), 7.78 (dd, 1H, J=5.1 Hz, J=1.3 Hz, ArH), 7.89 (d, 1H, J= 0.6 Hz, ArH), 8.55 (dd, 1H, J=5.1 Hz, J=0.6 Hz, ArH).
