Water → 3-Cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-(4,4-diethoxy-1-hydroxybut-2-ynyl)pyrazole

Beteiligte Stoffe

Reaktionsschritte

To a solution of propionaldehyde diethyl acetal (0.0192 g) in anhydrous tetrahydrofuran (2 ml) cooled to -78° C. under an atmosphere of nitrogen was added dropwise n-butyl lithium (62 μl, 2.5M in hexanes) and the mixture was stirred for 10 minutes. 3-Cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-formylpyrazole (0.05 g) was added and stirring continued for 30 minutes. The reaction mixture was poured into water (5 ml) and ether (5 ml). The organic layer was separated, dried (Na2SO4) and evaporated. The residue was purified by column chromatography on silica gel (5 g) eluted with dichloromethane. Combination and evaporation of suitable fractions gave the title compound as a white foam.

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