Water → 5-Acetyloxy-1-(4-t-butylphenyl)-3-methyl-1H-pyrazole

Participants

Reaction Steps

1-(4-t-Butylphenyl)-5-hydroxy-3-methyl-1H-pyrazole (21.7 g, 94.1 mmol) in tetrahydrofuran (600 mL) was mixed with triethylamine (26.2 mL, 188 mmol.) and acetyl chloride (7.4 mL, 104 mmol) at 0° C. and stirred at room temperature for 45 minutes. The reaction solution was mixed with water (300 mL), and the aqueous layer and the organic layer were separated. The solvent was removed from the organic layer by distillation, and the residue was mixed with ethyl acetate. The aqueous layer was extracted with ethyl acetate twice, and the extract was combined with the organic layer. The combined organic layer was washed with saturated aqueous sodium hydrogen carbonate once, with water twice and with saturated aqueous sodium chloride, dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated to give 22.2 g of the desired product (87% yield).

Provenance & Evidence