Antipyrine → 4-Tert-butyl-1,5-dimethyl-2-phenyl-1,2-dihydro-pyrazol-3-one

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution tert-butanol (800 μL) and 1,5-dimethyl-2-phenyl-1,2-dihydro-pyrazol-3-one (0.150 g) in dichloroethane (1 mL) was added boron trifluoride diethyletherate (400 μL). The reaction was heated to 40° C. over seven days. The reaction mixture was then cooled and poured onto an ice/water mixture, was basified to pH 10 using sodium hydroxide solution and was extracted with EtOAc. The solution was acidified with AcOH to pH=4 and further extracted with EtOAc. The combined organic phases were washed with brine and dried over sodium sulfate. Filtration and evaporation of the volatiles in vacuo afforded a crude residue which was purified via flash column chromatography to afford 4-tert-butyl-1,5-dimethyl-2-phenyl-1,2-dihydro-pyrazol-3-one (0.025 mg) as a white solid. MS (ESI+): 245.4 [M+H]+).

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