111042-91-2

To a stirred solution of 3-chloro-4-cyanopyridine (6.2 g, 44.92 mmol) in acetonitrile (60 mL) was sequentially added methyl mercaptoacetate (4.26 mL, 47.173 mmol) and potassium carbonate (12.4 g, 89.855 mmol). The reaction mixture was stirred and refluxed at 25 °C for 3 hours. After completion of the reaction, the mixture was concentrated under reduced pressure. The resulting residue was diluted with distilled water (100 mL) and extracted with ethyl acetate (4 x 200 mL). The organic layers were combined, dried with anhydrous sodium sulfate and concentrated under reduced pressure to give the crude product. The crude product was purified by n-pentane milling to afford methyl 3-aminothieno[2,3-c]pyridine-2-carboxylate (7.5 g, 36.016 mmol, 80% yield) as a light yellow solid.LC-MS (ESI+): m/z 209 [M+H]+.

[1] Patent: WO2014/186035, 2014, A1. Location in patent: Page/Page column 183
[2] Journal of Heterocyclic Chemistry, 1987, vol. 24, p. 85 - 89