N-methyl-2-pyrrolidone → 4-[5-(4-Chlorophenyl)-2-ethylphenyl]-5-hydroxy-2,6-dimethyl-2,3-dihydro-3-pyridazinone

Participants

Reaction Conditions

Reaction Steps

To a 25 ml volume three-necked flask, 4-[5-(4-chlorophenyl)-2-ethylphenyl]-2,6-dimethyl-5-methylsulfonyl-2,3-dihydro-3-pyridazinone ((2-34)-(1)-67) (290 mg), N-methyl-2-pyrrolidone (890 mg), and aqueous sodium hydroxide solution (410 mg) were added under a nitrogen atmosphere, and stirred at 70° C. for 3 hours. After the reaction mixture was cooled to room temperature, toluene was added and washed. The organic layer was removed. To the resulting aqueous layer, 10 wt % of hydrochloric acid was added to adjust pH to less than 1, and extracted with ethyl acetate 3 times. The organic layers were combined, washed with saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was subjected to column chromatography (hexane: ethyl acetate=2:1) to give 157 mg of 4-[5-(4-chlorophenyl)-2-ethylphenyl]-5-hydroxy-2,6-dimethyl-2,3-dihydro-3-pyridazinone ((1-4)-(1)-67).

Provenance & Evidence