Hydrochloric Acid → HCID 13823607, compound

Participants

Reaction Steps

[2,6-Dichloro-4-(trifluoromethyl)phenyl]hydrazine (5 g) and ethyl (2-ethoxymethylene)acetoacetate (3.8 g) synthesized according to the method described in J. Chem. Soc. Perkin trans. I, p. 1875 (1988) were added to a mixed solvent of 1 N hydrochloric acid aqueous solution (90 ml) and ethanol (100 ml), and stirred for 4 hours under reflux. After completion of the reaction, the mixture was allowed to cool, ethanol was evaporated, and extracted with ethyl acetate. The organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and then the solvent was evaporated. The obtained residue was purified with silica gel column chromatography (n-hexane/ethyl acetate) to give 1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-5-methyl-1H-pyrazole-4-carboxylic acid ethyl ester (5.83 g) as a yellow oil. MS (ESI) m/z: 367, 369 (M+H)+.

Provenance & Evidence