Studies on Heterocyclic Compounds. XXII. The Reaction of Oxazolo [3, 2-b] pyridazinium Perchlorates with Hydroxylamines

Abstract

The reaction of oxazolo [3, 2-b] pyridazinium perchlorates (I) with hydroxylamine hydrochloride and potassium hydroxide in N, N-dimethylformamide afforded 2-(2, 3-dihydro-3-hydroxyimino-2-pyridazinyl) ethanones (II) and 2-(2, 3-dihydro-3-hydroxyimino-2-pyridazinyl) ethanone oximes (III), from both of which imidazo [1, 2-b] pyridazine 1-oxides (IV) were synthesized by heating in meneral acid. The N-oxides were characterized by converting them into the corresponding imidazopyridazines by deoxygenation.