反应详情

An intimate mixture of 3-cyano-5,6-dimethyl-2-hydroxypyridine (42 g) and phosphorous pentachloride (81 g) was heated at 140°-160° for 2 hours. Phosphoryl chloride was removed by distillation under reduced pressure and ice-water (500 g) was added to the residue. The mixture was adjusted to pH 7 with aqueous sodium hydroxide and extracted with ether. The ether extracts were evaporated to an oil which was crystallised from ether-light petroleum (b.p. 60°-80°) to give 2-chloro-3-cyano-5,6-dimethylpyridine (25.3 g), m.p. 83°-7°.

1. temperaturewas heated at 140°-160° for 2 hours
2. customPhosphoryl chloride was removed by distillation under reduced pressure and ice-water (500 g)
3. additionwas added to the residue
4. extractionextracted with ether
5. customThe ether extracts were evaporated to an oil which
6. customwas crystallised from ether-light petroleum (b.p. 60°-80°)