反应详情

The 2-hydroxy-3-p-methoxyphenylpyrazine is refluxed (120°-130° C.) with excess phosphorus oxychloride under stirring for 3-5 hours. The solution is evaporated to dryness at 50° C. in vacuo, cooled, ice is added, then treated with 10% sodium hydroxide solution, extracted with a suitable solvent such as diethyl ether, the ethereal solution washed with water and evaporated. The crude product is crystallized from a suitable solvent such as ethanol to give 2-chloro-3-p-methoxyphenylpyrazine.

1. customThe solution is evaporated to dryness at 50° C. in vacuo
2. temperaturecooled
3. additionice is added
4. additiontreated with 10% sodium hydroxide solution
5. extractionextracted with a suitable solvent such as diethyl ether
6. washthe ethereal solution washed with water
7. customevaporated
8. customThe crude product is crystallized from a suitable solvent such as ethanol