849807-09-6

To a dichloromethane solution of 2-chloroquinoline-6-carboxylic acid (4.0 g, 20 mmol) and N,N-dimethylformamide (8 ml) was slowly added sulfoxide chloride (8 ml) at 0°C and the reaction mixture was stirred for 5 hours at room temperature. After completion of the reaction, the mixture was concentrated to give a residue. The residue was dissolved in dichloromethane (50 ml) and washed with saturated sodium bicarbonate solution (20 ml) and stirred for 30 minutes. The organic layer was separated and concentrated to give the crude product. The crude product was purified by silica gel column chromatography to afford methyl 2-chloroquinoline-6-carboxylate (1.3 g, 30% yield) as a white solid.

[1] European Journal of Organic Chemistry, 2016, vol. 2016, # 8, p. 1606 - 1611
[2] Patent: US2014/128391, 2014, A1. Location in patent: Paragraph 0188; 0191; 0192; 0282; 0285; 0286
[3] Bioorganic and Medicinal Chemistry Letters, 2010, vol. 20, # 12, p. 3573 - 3578
[4] Heterocycles, 2011, vol. 83, # 7, p. 1649 - 1658
[5] Patent: WO2016/7423, 2016, A1. Location in patent: Page/Page column 45