反应详情

4 g. lead tetraacetate were suspended in 40 ml. glacial acetic acid, 1.5 g. of the hydrazone obtained from 1.55 g. 5-nitro-1-methyl-imidazole-2-aldehyde and 1.1 g. 3-hydrazinopyridazine hydrochloride (prepared by heating for 30 minutes in 20 ml. 50 percent aqueous methanol at 50° C. and subsequent neutralization with sodium acetate) were added, while stirring at 50° - 60° C., the reaction mixture further stirred for 15 minutes, considerably evaporated in a vacuum, the resultant crystals filtered off with suction, triturated with water and dried for 2 hours in a vacuum at 120° C., 1.05 g. of the desired 3-(5-nitro-1-methyl-2-imidazolyl)-s-triazolo[4,3-b]pyridazine being obtained, which has a melting point of 235° - 237° C.

1. stirringthe reaction mixture further stirred for 15 minutes
2. customconsiderably evaporated in a vacuum
3. filtrationthe resultant crystals filtered off with suction
4. customtriturated with water
5. customdried for 2 hours in a vacuum at 120° C.