反应详情

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.

1. extractionthe mixture was extracted with ethyl acetate
2. dry with materialThe ethyl acetate layer was dried over anhydrous magnesium sulfate
3. concentrationconcentrated
4. customThe residue was purified by silica gel column chromatography (10%-65% ethyl acetate/hexane)
5. customto give colorless crystals
6. stirringUnder an atmospheric hydrogen atmosphere, the mixture was stirred at room temperature for 2 hr
7. filtrationThe catalyst was filtered off
8. concentrationthe filtrate was concentrated