反应详情

To a solution of 5-chloro-nicotinic acid (20.0 g, 127 mmol, purchased from Matrix Scientific, Columbia, S.C., USA) in methanol (200 mL) at 0° C. was added thionyl chloride (18.6 mL, 255 mmol). The reaction mixture was refluxed for 4 hours. After cooling to room temperature the mixture was diluted with saturated aqueous sodium bicarbonate, extracted with AcOEt (3×300 mL), dried over sodium sulfate, filtered and concentrated under reduced pressure to afford crude 5-chloro-nicotinic acid methyl ester (17.2 g, 79%). 1H NMR (400 MHz, CDCl3) δ ppm 9.10 (d, J=1.4 Hz, 1 H), 8.75 (d, J=2.3 Hz, 1 H), 8.29 (d, J=2.0 Hz, 1H), 3.98 (s, 3 H). MS m/z 171.8

1. temperatureThe reaction mixture was refluxed for 4 hours
2. extractionextracted with AcOEt (3×300 mL)
3. dry with materialdried over sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated under reduced pressure