1: With hydrazine hydrate in tetrahydrofuran Heating; 2: With PPA in tetrahydrofuran T=130°C; 3 h;

zinc(II) chloride in acetonitrile 7 h; Heating;

zinc(II) chloride in acetonitrile 7 h; Heating;

triethylamine in dichloromethane T=-22°C; 0.5 h;

1: 2-benzoyl-4,5-dichloropyridazin-3(2H)-one With hydrazine hydrate in tetrahydrofuran T=20°C; 0.166667 h; 2: 4,5-dichloro-2-(4-chloro-benzoyl)-2H-pyridazin-3-one in tetrahydrofuran T=20°C; 0.166667 h;