97509-75-6

Light yellow Cryst

2-Cyano-3-fluoropyridine is an organic intermediate that can be prepared from 3-fluoropyridine in three steps.

Using 3-fluoropyridine-N-oxide (Intermediate A, 2.85 g, 25.2 mmol) and trimethylcyanosilane (10.0 mL, 75.6 mmol) as raw materials, Intermediate A was dissolved in dichloromethane (25 ml) at room temperature, followed by addition of trimethylcyanosilane. The reaction mixture was heated to reflux for 10 hours. After completion of the reaction, it was cooled to room temperature and the reaction was quenched by the addition of saturated aqueous sodium bicarbonate solution (30 mL). The reaction mixture was extracted with dichloromethane (3 x 150 mL), the organic phases were combined and dried over anhydrous sodium sulfate. After filtration, the organic phase was concentrated under reduced pressure to give a light brown oily crude product (4.60 g). The crude product was purified by rapid column chromatography on silica gel, the eluent was hexane solution of 30% ethyl acetate to give a light brown oil, which solidified to light brown solid product B (2.48 g, 84% yield) after standing. The product was analyzed by HPLC with a retention time of 1.03 min.

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[2] Chemical and Pharmaceutical Bulletin, 1985, vol. 33, # 2, p. 565 - 571
[3] Patent: WO2006/12374, 2006, A1. Location in patent: Page/Page column 213
[4] Patent: US2004/77605, 2004, A1
[5] Patent: US2003/232842, 2003, A1. Location in patent: Page 7-8