3,5-Dichloro-1-methylpyrazole-4-carbonyl chloride → 2-{2-Tert-butyloxazol-4-yl}-3-(3,5-dichloro-1-methyl-pyrazol-4-yl)-3-hydroxyacrylonitrile

Participants

Reaction Steps

2.87 g of potassium tert-butoxide was suspended in 20 ml of THF, and a solution of 2.00 g of 2-tert-butyl-4-cyanomethyloxazole and 2.37 g of 3,5-dichloro-1-methylpyrazole-4-carbonyl chloride as dissolved in 10 ml of THF was dropwise added thereto with cooling with ice, and then stirred overnight at room temperature. The reaction mixture was poured into ice water, extracted with ethyl acetate, and washed with a small amount of water. After the resulting product was dried with anhydrous sodium sulfate, the solvent was evaporated out under reduced pressure. The residual product was purified through column chromatography (silica gel; n-hexane:ethyl acetate=4:1) to obtain 3.26 g of the intended compound.

Provenance & Evidence