Acetaldehyde → 3-(4-Chlorophenyl)-4,5-dihydro-N-(4-(methylthio)phenyl)-4-(5-trifluoromethyl-2-pyridinyl)-1H-pyrazole-1-carboxamide

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Reaction Steps

4-(Methylthio)phenyl isocyanate (2.8 g, 17 mmol) was added to a stirring slurry of 3.8 g (3.0 mmol) of the product of Example 6 in methylene chloride (25 mL) at 21° C. causing rapid formation of a pale precipitate. TLC showed complete conversion after 19 hr and the precipitate, which was the corresponding bisaryl urea, was removed by gravity filtration. The filtrate was diluted with saturated aqueous sodium bicarbonate and the layers separated. The organic layer was dried over sodium sulfate, filtered, and evaporated to obtain a red oil which solidified on standing. This was purified by column chromatography eluting with 100:0 to 90:10 methylene chloride/ethyl acetate solvent. The product was recrystallized by dissolving in ethyl acetate and then adding hexane to obtain 0.44 g (29 percent of theory; 9 percent from the ethanone) of the title compound as fine white needles melting at 225°-226° C.;

Provenance & Evidence