Phenylhydrazine → 1-[4-(methylsulfonyl)phenyl]-3-(1-phenyl-1H-pyrazol-5-yl)pyridazin-4(1H)-one

Participants

Reaction Steps

To a solution of 3-[3-(dimethylamino)prop-2-enoyl]-1-[4-(methylsulfonyl)phenyl]pyridazin-4(1H)-one (crude 615 mg, 1.77 mmol) in 20 mL of methanol was added phenylhydrazine (765 mg, 7.08 mmol). The mixture was, refluxed for 4 h and concentrated. The residue was dissolved in dichloromethane (20 mL), washed with 1N HCl aqueous solution and brine, dried over Na2SO4, and concentrated under reduced pressure. The residue was purified by prep-HPLC to give 1-[4-(methylsulfonyl)phenyl]-3-(1-phenyl-1H-pyrazol-5-yl)pyridazin-4(1H)-one (42 mg, 6% for two steps) as a yellow solid.

Provenance & Evidence