Dimethylformamide → 1-methyl-3-trifluoromethyl-1H-pyrazole-4-carboxylic acid (4'-chlorobiphenyl-2-yl) amide

Participants

Reaction Steps

A solution of 1-methyl-3-trifluoromethyl-1H-pyrazole-4-carboxylic acid (0.68 g) and oxalyl chloride (0.49 g) in methylene chloride (30 ml) is stirred for 2 hours at room temperature in the presence of a catalytic amount of DMF. The resulting acid chloride solution is then added to a solution of 4′-chlorobiphenyl-2-ylamine (0.71 g) and triethylamine (0.36 g) in 15 ml of methylene chloride at 0° C. The reaction mixture is then stirred for 4 hours at room temperature. After distilling off the solvent in a water-jet-vacuum, the residue is taken up in ethylacetate/water. The ethylacetate phase is extracted twice with water. After drying of the organic phase with Na2SO4, the solvent is distilled off in a water-jet-vacuum and the residue purified by column chromatography (silica gel; eluant: ethylacetate/hexane=1:1). 0.8 g of 1-methyl-3-trifluoromethyl-1H-pyrazole-4-carboxylic acid (4′-chlorobiphenyl-2-yl) amide are obtained in the form of slightly brownish crystals having a melting point of 144–146° C.

Provenance & Evidence