反应详情

To a mixture of ethyl 1,5-diphenyl-1H-pyrazole-4-carboxylate (14.9 g) and tetrahydrofuran (250 ml) was added dropwise diisobutylaluminum hydride (1 mol/l toluene solution, 120 ml) under ice-cooling. The reaction mixture was stirred at room temperature for 1 hr. and poured into a 1N aqueous hydrochloric acid solution. The mixture was extracted with ethyl acetate. The ethyl acetate layer was washed successively with a 1N aqueous hydrochloric acid solution and saturated brine, dried over anhydrous magnesium sulfate, and concentrated to give (1,5-diphenyl-1H-pyrazol-4-yl)methanol (12.6 g, 99%) as colorless crystals. Recrystallization thereof from ethyl acetate-hexane gave colorless prism crystals. melting point: 147-148° C.

1. temperaturecooling
2. extractionThe mixture was extracted with ethyl acetate
3. washThe ethyl acetate layer was washed successively with a 1N aqueous hydrochloric acid solution and saturated brine
4. dry with materialdried over anhydrous magnesium sulfate
5. concentrationconcentrated