Synthesis
To a solution of 3-ethoxycarbonylpyridine N-oxide dissolved in 330 mL of dichloromethane (DCM) was added trimethylmethylsilyl cyanide (TMSCN) (11.0 g, 65.9 mmol, 1.0 eq.) and dimethylcarbamoyl chloride (7.1 g, 65.9 mmol, 1.0 eq.) in that order. The reaction mixture was stirred at room temperature for 48 hours. Subsequently, the reaction mixture was adjusted to alkaline by slowly adding a 10% solution of potassium carbonate (K2CO3). The organic layer was separated, dried with anhydrous sodium sulfate and concentrated under reduced pressure to give the crude product. The crude product was purified by column chromatography to afford ethyl 6-cyanonicotinate (compound A, 5.7 g) and ethyl 2-cyanonicotinate (compound B, 3.5 g).
References
[1] Chemical and Pharmaceutical Bulletin, 1985, vol. 33, # 2, p. 565 - 571
[2] Patent: WO2013/102142, 2013, A1. Location in patent: Paragraph 0141
[3] Patent: WO2013/102145, 2013, A1. Location in patent: Paragraph 0247
[4] Patent: US2015/344483, 2015, A1. Location in patent: Paragraph 0474; 0475
