反应详情

A mixture of 2-(4-fluorophenyl)-6-hydroxy-3,4′-bipyridine-5-carbonitrile (6.57 g, 22.5 mmol, obtained in reference example 10), POCl3 (26.3 mL, 287.5 mmol) and DMF (0.37 mL) was heated to reflux under argon atmosphere for 2 h. It was cooled with an ice bath and basified by adding 30% aqueous NH3. The precipitate obtained was filtered and washed with water. The product was purified by chromatography on silica gel using hexane-EtOAc mixtures of increasing polarity as eluent, to afford 3.86 g of the desired product as a yellow solid (yield: 55%).

1. temperaturewas heated
2. temperatureto reflux under argon atmosphere for 2 h
3. temperatureIt was cooled with an ice bath
4. customThe precipitate obtained
5. filtrationwas filtered
6. washwashed with water
7. customThe product was purified by chromatography on silica gel
8. temperatureof increasing polarity as eluent