Synthesis
6-Carbamoylpyridine-2-carboxylic acid (compound G1) (500 mg, 3 mmol) was mixed with phosphoryl chloride (POCl3) (15 mL) and heated to reflux temperature for 2 hours. After completion of the reaction, the reaction mixture was processed according to conventional methods, and the resulting crude product could be used for subsequent reactions without further purification. Yield: 280 mg (63%), melting point: 180-181 °C.
References
[1] Patent: WO2006/589, 2006, A1. Location in patent: Page/Page column 57-58
[2] Patent: EP2533783, 2015, B1. Location in patent: Paragraph 0451-0452
