Reaktion #595105

Reaktionsgleichung

water

benzyltriphenylphosphonium bromide

potassium carbonate

3-[4-(Trifluoromethyl)phenyl]-1H-pyrazole-5-carbaldehyde

→

title compound

Ausbeute 56.0%

5-(2-phenylethyl)-3-[4-(trifluoromethyl)phenyl]-1H-pyrazole

Ausbeute 56.0%

Lösungsmittel

tetrahydrofuran

N,N-dimethylformamide

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Extraktionthe mixture was extracted with ethyl acetate
2. 2
   TrocknenThe ethyl acetate layer was dried over anhydrous magnesium sulfate
3. 3
   Einengenconcentrated
4. 4
   SonstigeThe residue was purified by silica gel column chromatography (10%-65% ethyl acetate/hexane)
5. 5
   Sonstigeto give colorless crystals
6. 6
   workup.STIRRINGUnder an atmospheric hydrogen atmosphere, the mixture was stirred at room temperature for 2 hr
7. 7
   FiltrationThe catalyst was filtered off
8. 8
   Einengenthe filtrate was concentrated

Vorschrift

3-[4-(Trifluoromethyl)phenyl]-1H-pyrazole-5-carbaldehyde (1.20 g, 5.0 mmol) was dissolved in N,N-dimethylformamide (10 mL), and benzyltriphenylphosphonium bromide (3.25 g, 7.5 mmol) and potassium carbonate (2.76 g, 20.0 mmol) were added. The mixture was stirred at room temperature for 14 hr. The reaction mixture was poured into water, and the mixture was extracted with ethyl acetate. The ethyl acetate layer was dried over anhydrous magnesium sulfate and concentrated. The residue was purified by silica gel column chromatography (10%-65% ethyl acetate/hexane) to give colorless crystals. The colorless crystals were dissolved in tetrahydrofuran (30 mL) and ethanol (30 mL), and 10% palladium-carbon (50% water-containing product, 500 mg) was added. Under an atmospheric hydrogen atmosphere, the mixture was stirred at room temperature for 2 hr. The catalyst was filtered off, and the filtrate was concentrated to give the title compound (880 mg, yield 56%, 2 steps) as colorless crystals.

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