反应详情

To 30 parts of a sulfuric acid solution in water (90:10 by volume) were added portionwise during a period of 5 minutes 2 parts of 2-chloro-α-(4-chlorophenyl)-4-(4,5-dihydro-3,5-dioxo-1,2,4-triazin-2(3H)-yl)benzeneacetonitrile at room temperature. Upon completion, stirring was continued for 2 hours at 80° C. The reaction mixture was poured into ice water. The product was filtered off, washed with water and purified by column chromatography over silica gel using a mixture of trichloromethane and methanol (95:5 by volume) as eluent. The pure fractions were collected and the eluent was evaporated in vacuo. The residue was stirred in 2,2'-oxybispropane. The product was filtered off and dried, yielding 1.1 parts (54%) of 2-chloro-α-(4-chlorophenyl)-4-(4,5-dihydro-3,5-dioxo-1,2,4-triazin-2(3H)-yl)-benzeneacetamide; mp. 160.7° C. (intermediate 26).

1. filtrationThe product was filtered off
2. washwashed with water
3. custompurified by column chromatography over silica gel using
4. additiona mixture of trichloromethane and methanol (95:5 by volume) as eluent
5. customThe pure fractions were collected
6. customthe eluent was evaporated in vacuo
7. stirringThe residue was stirred in 2,2'-oxybispropane
8. filtrationThe product was filtered off
9. customdried