| Abstract: | Multi-substituted-1-(1-bromo-2-oxopropyl)pyridazin-6-ones 3, 4 , multi-substituted-1-(1,1-dibromo-2-oxopropyl)pyridazin-6-ones 7, 8 , and multi-substituted-1-(3-bromo-2-oxopropyl)pyridazin-6-ones 5, 6 were synthesized from the corresponding 1-(2-oxopropyl)pyridazin-6-ones 1, 2 by the selective bromination in acidic or neutral medium. And treatment of 1,1-dibromo-2-oxopropyl derivatives 7, 8 with aqueous potassium carbonate gave the corresponding pyridazin-6-ones 9, 10 by the dealkylation. Reaction of 1 with methanolic potassium cyanide afforded only the corresponding 4-methoxy derivative 11 , whereas reaction of 2 with methanolic potassium cyanide gave 4-methoxy derivative 12 and 2-cyano-2-hydroxypropyl derivative 13 . Reaction of 1 and 2 with hydroxylamine in methanol afforded the corresponding syn-2-hydroxyiminopropyl derivatives 14 and 15 . |
