3-chloro-4-[chloro(4-chlorophenyl)methyl]phenyl-1,2,4-triazine-3,5(2H,4H)-dione → Clazuril

Participants

Reaction Conditions

Reaction Steps

A mixture of 12 parts of 2-[3-chloro-4-[chloro(4-chlorophenyl)methyl]phenyl]-1,2,4-triazine-3,5(2H,4H)-dione and 5.4 parts of copper cyanide was stirred and heated first for 3 hours at 130° C. and for 3 hours at 180° C. After cooling, the precipitated product was dissolved in a mixture of trichloromethane and methanol (90:10 by volume). The inorganic precipitate was filtered off and the filtrate was evaporated in vacuo. The residue was purified four times by column chromatography over silica gel using first a mixture of trichloromethane and acetonitrile (90:10 by volume), second a mixture of tetrachloromethane and methanol (93:7 by volume) and then twice a mixture of tetrachloromethane and acetonitrile (95:5 by volume) as eluent. The pure fractions were collected and the eluent was evaporated. The residue was further purified by column chromatography (HPLC) over silica gel using a mixture of trichloromethane and methanol (98:2 by volume) as eluent. The pure fractions were collected and the eluent was evaporated in vacuo. The residue was dried, yielding 1.3 parts (11.2%) of 2-chloro-α-(4-chlorophenyl)-4-(4,5-dihydro-3,5-dioxo-1,2,4-triazin-2(3H)-yl)benzeneacetonitrile; mp. 196.8° C. (compound 22).

Provenance & Evidence