反应详情

To a stirred and cooled (10° C.) mixture of 20 parts of 3-[(2-amino-6-chlorophenyl)amino]-1-propanol, 12 parts of a hydrochloric acid solution and 100 parts of water is added dropwise a solution of 9 parts of potassium cyanate in 30 parts of water. Upon completion, stirring is continued first for 2 hours at room temperature and further overnight at reflux temperature. After cooling, the product is extracted with trichloromethane. The extract is washed with a diluted hydrochloric acid solution, dried, filtered and evaporated. The residue is crystallized from 4-methyl-2-pentanone, yielding 9 parts (41%) of 4-chloro-1,3-dihydro-3-(3-hydroxypropyl)-2H-benzimidazol-2-one.

1. temperaturecooled
2. stirringUpon completion, stirring
3. temperatureat reflux temperature
4. temperatureAfter cooling
5. extractionthe product is extracted with trichloromethane
6. washThe extract is washed with a diluted hydrochloric acid solution
7. customdried
8. filtrationfiltered
9. customevaporated
10. customThe residue is crystallized from 4-methyl-2-pentanone