Thionyl Chloride → HCID 54495530, compound

Participants

Reaction Steps

A slurry of 12.0 g (0.0343 mole) of 1-(2,6-dichloro-4-trifluoromethylphenyl)-4-cyano-1H-5-pyrazolylcarboxylic acid in 30 mL (49 g, 0.41 mole) of thionyl chloride was heated at gentle reflux for approximately 62 hours, after which it had become a dark solution. This solution was cooled, and the excess thionyl chloride was evaporated under reduced pressure, leaving a residue. Petroleum ether was added to this residue, causing a precipitate, which, upon filtration, yielded 7.4 g of 1-(2,6-dichloro-4-trifluoromethylphenyl)-4-cyano-1H-5-pyrazolylcarboxylic acid chloride as a solid, mp 100°-102° C. The NMR spectrum was consistent with the proposed structure. A second crop of tacky crystals was obtained by chilling the filtrate obtained when the product was isolated by filtration. The NMR spectrum of the second crop of crystals was consistent with the proposed structure, but showed also that it was contaminated with some starting material.

Provenance & Evidence