Benzoylacetone → HCID 22346892, compound

Participants

Reaction Steps

To a solution of 1-benzoylacetone (3.63 g, 0.0224 mol) and N,N-diisopropylethylamine (2.88 g, 0.0224 mol) in anhydrous methanol (160 mL), 4-bromophenylhydrazine hydrochloride was added and the resulting mixture was stirred at ambient temperature for 20 hours. The solvent was removed under reduced pressure and the resulting mixture was partitioned between a 5% solution of citric acid solution in water (200 mL) and ethyl acetate (150 mL). The organic phase was successively washed with water (2×200 mL) and brine (150 mL), dried with magnesium sulfate and concentrated. The resulting residue was purified by flash chromatography on silica using ethyl acetate/n-heptane (5:95) as mobile phase to yield 1-(4-bromophenyl)-3-methyl-5-phenyl-4,5-dihydro-1H-pyrazole (4.05 g, 0.0129 mol) as an off-white solid.

Provenance & Evidence