Synthesis
A 100 mL round bottom flask was charged with 6-bromonicotinic acid (540 mg, 2.7 mmol), methylene chloride (20 mL) and N,N-dimethylformamide (1 drop). Oxalyl chloride (1 mL) was then added slowly and vigorous gas escape was observed. The reaction mixture was stirred at room temperature for 1 h, after which the solvent was removed under reduced pressure by rotary evaporator. The residue was treated with methanol (MeOH) and the solvent was again removed under reduced pressure. The residue was dissolved in dichloromethane and washed with saturated sodium bicarbonate (NaHCO3) solution. The organic layer was dried with anhydrous sodium sulfate (Na2SO4), filtered and concentrated under reduced pressure to give 369 mg of methyl 6-bromonicotinate in 55% yield. The product was characterized by 1H NMR (500 MHz): δ 9.00 (dd, J = 2.0, 0.5 Hz, 1H), 8.25 (dd, J = 8.5, 2.5 Hz, 1H), 7.42 (dd, J = 8.5, 0.5 Hz, 1H), 3.96 (s, 3H).
References
[1] Journal of the American Chemical Society, 2011, vol. 133, # 34, p. 13445 - 13454
[2] Heterocycles, 1994, vol. 38, # 7, p. 1551 - 1572
[3] Patent: WO2008/21388, 2008, A1. Location in patent: Page/Page column 191-192
[4] Patent: WO2018/126072, 2018, A1. Location in patent: Paragraph 0255; 0256
[5] Patent: US2014/18368, 2014, A1. Location in patent: Paragraph 0162; 0174
