4,4,4-Trifluoro-1-(2-furanyl)-1,3-butanedione → 1-(2-Chlorophenyl)-5-(furan-2-yl)-3-(trifluoromethyl)-1H-pyrazole

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Into a 500 mL flask was weighed 25.0 g (139.6 mmol) of 2-chlorophenylhydrazine hydrochloride, 27.4 g (153 mmol) of 4,4,4-trifluoro-1-furan-2-yl-butane-1,3-dione, and 200 mL of acetic acid. The resulting solution was heated at 80° C. for 18 h then was cooled and was washed into a separatory funnel with 1.0 M NaOH and ethyl acetate. The ethyl acetate was separated, washed with 1.0 M NaOH, brine, dried (Na2SO4), and was concentrated in vacuo. The residue was filtered through a short column of silica gel affording 1-(2-chlorophenyl)-5-furan-2-yl-3-trifluoromethyl-1H-pyrazole as a brown oil, yield: 37.31 g (85%); MS (ES): 313 [M+H]+.

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