Thioglycolic Acid → alpha-(4-chlorophenyl)-4-(4,5-dihydro-3,5-dioxo-1,2,4-triazin-2(3H)-yl)-3-methoxybenzeneacetonitrile

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Reaction Conditions

Reaction Steps

A mixture of 4.2 parts of 2-[4-[(4-chlorophenyl)cyanomethyl]-3-methoxyphenyl]-2,3,4,5-tetrahydro-3,5-dioxo-1,2,4-triazine-6-carboxylic acid and 13 parts of 2-mercaptoacetic acid is stirred and heated for 2 hours at 175° C. After cooling, 150 parts of water are added. The aqueous phase is decanted and the remaining oil is stirred in water. The whole is treated with sodium hydrogen carbonate. The product is extracted with a mixture of trichloromethane and methanol (90:10 by volume). The extract is dried, filtered and evaporated. The residue is purified by column chromatography over silica gel using a mixture of trichloromethane and methanol (97:3 by volume) as eluent. The pure fractions are collected and the eluent is evaporated in vacuo. The residue is crystallized from 8 parts of acetonitrile. The product is filtered off, washed with 2,2'-oxybispropane and dried, yielding α-(4-chlorophenyl)-4-(4,5-dihydro-3,5-dioxo-1,2,4-triazin-2(3H)-yl)-3-methoxybenzeneacetonitrile (intermediate 2).

Provenance & Evidence