4,5-Dichloro-3(2H)-pyridazinone is used as a new labelled substituted pyridazinone with tuberculostatic action.
The solid phase FT-IR and FT-Raman spectra of 4,5-dichloro-3-hydroxypyridazine was studied.
4,5-Dichloro-3(2H)-pyridazinone causes skin irritation and serious eye irritation, it may cause respiratory irritation.
Hydrazine sulfate (305.7 g, 2.35 mol) was added to a solution of 3,4-dichloro-5-hydroxy-5H-furan-2-one (419 g, 2.48 mol) and sodium acetate (212 g, 2.58 mol) in water (600 mL). The mixture was stirred under reflux for 4 h. After filtration and evaporation, the residual solid was recrystallized from ethanol to provide 4,5-dichloropyridazin-3(2H)-one (216 g, 67%) as an off-white solid.
