Patent ID: 7141678

Claim:
A process for the preparation of a 1-(4-sulfonylphenyl)pyrazole or a salt thereof, the process comprising forming 1-(4-sulfonylphenyl)pyrazole or a salt thereof by the reaction of a 1,3-diketone or a salt thereof with a 4-sulfonylphenylhydrazine or a salt thereof in a reaction mixture comprising a solvent system, the reaction mixture being formed by combining a source of the 1,3-diketone or salt thereof, a source of the 4-sulfonylphenylhydrazine or salt thereof, and the solvent system, wherein (i) the 1,3-diketone source and (ii) mixture(s) which may be formed by combining the 1,3-diketone source with the solvent system before the 1,3-diketone source or solvent system is combined with the 4-sulfonylphenylhydrazine source contain less than 30 equivalents of water per equivalent of 1,3-diketone or salt thereof, and crystalizing a solid reaction product containing the 1-(4-sulfonylphenyl)pyrazole, or a salt thereof, from the reaction mixture, the 1-(4-sulfonylphenyl)pyrazole, or salt thereof, constituting at least about 98% by weight of the solid reaction product, wherein the 1,3-diketone has the formula: the 4-sulfonylphenylhydrazine has the formula: the 1-(4-sulfonylphenyl)pyrazole has the formula: R 1 is an ester or a hydrocarbyl substituted with one or more halogens; R 2 is hydrogen, alkyl, cyano, hydroxyalkyl, cycloalkyl or alkylsulfonyl; R 3 is phenyl substituted with one or more of an alkyl, a halogen, an ether, an acid or an acid ester; and R 5 is methyl, amino or substituted amino.