Synthesis
General procedure for the synthesis of methyl 3-quinolinecarboxylate from methanol and quinoline-3-carboxylic acid: quinoline-3-carboxylic acid (3 g, 17.32 mmol) was dissolved in methanol (30 mL) and cooled at 0°C in an ice bath. Subsequently, thionyl chloride (1.264 mL, 17.32 mmol) was added slowly and dropwise, then the reaction mixture was heated to 80°C and kept overnight. The reaction progress was monitored by thin layer chromatography (TLC). Upon completion of the reaction, the methanol was evaporated under reduced pressure and the resulting residue was alkalized with saturated sodium bicarbonate solution to pH 7 to 8, precipitating a white solid. After filtration and drying, methyl 3-quinolinecarboxylate (3.2 g, 99% yield) was obtained as a white solid; mass spectrometry (M/Z) showed a molecular ion peak of 187.3.
References
[1] Patent: WO2014/33604, 2014, A1. Location in patent: Page/Page column 48
[2] Organic and Biomolecular Chemistry, 2016, vol. 14, # 24, p. 5505 - 5510
[3] Tetrahedron Asymmetry, 2013, vol. 24, # 18, p. 1142 - 1147
[4] Patent: US2016/122303, 2016, A1. Location in patent: Paragraph 0078
[5] Tetrahedron Asymmetry, 2010, vol. 21, # 18, p. 2307 - 2313
