3(2H)-Pyridazinone,5-(1-piperazinyl)-(9CI) synthesis

Yield:159430-52-1 65%

Reaction Conditions:

with palladium hydroxide on carbon;hydrogen in methanol;lithium hydroxide monohydrate; under 3000.3 Torr; for 24 h;

Steps:

Compound 535: 5-(piperazin-1-yl)pyridazin-3(2H)-one

To solution of Compound 534 (18.5 g, 1.0 equiv) in a mixture MeOH (100 mL) I H2O (100 mL) was added palladium hydroxide 10-20 wt.% on charcoal (500 mg). The reaction mixture was stirred under hydrogen atmosphere (4 bars) for 24 hours. The reaction mixture was filtered over Celite. The filtrate was concentrated and triturated in MeOH to obtain Compound 535 (10.15g, 65%) as a white solid.

References:

WO2022/117882,2022,A2 Location in patent:Page/Page column 269