反应详情

Reflux a solution of 5-phenyl-1,3-dihydro-imidazo[4,5-b]pyrazin-2-one (200 mg) in phosphorus oxychloride (10 mL) for 18 hours. After cooling, remove the excess POCl3 in vacuo, and triturate the residue in ice-water (200 mL). After stirring for 30 minutes, filter the precipitate to obtain 2-chloro-5-phenyl-1H-imidazo[4,5-b]pyrazine as a gray solid.

1. temperatureAfter cooling
2. customremove the excess POCl3 in vacuo
3. customtriturate the residue in ice-water (200 mL)
4. filtrationfilter the precipitate