Pyridazine 1,2-Dioxide類の研究(第3報)3,6-Dimethylpyridazine 1,2-Dioxideの求核置換反応

抄録

3, 6-Dimethylpyridazine 1, 2-dioxide (I) was reacted with phosphoryl chloride, followed with sodium methoxide, to give 4-chloro-5-methoxy-3, 6-dimethylpyridazine (Va), 4, 5-dimethoxy-3, 6-dimethylpyridazine (VI), 3-methoxymethyl-4-methoxy-6-methylpyridazine (VII), and 3, 6-bis(methoxymethyl)pyridazine (VIII). It was presumed that 4, 5-dichloro-3, 6-dimethylpyridazine (II), 3-chloromethyl-4-chloro-6-methylpyridazine (III), and 3, 6-bis(chloromethyl)pyridazine (IV) were produced in the reaction. When the reaction of I carried out with phosphoryl bromide at room temperature, deoxygenation occurred and 3, 6-dimethylpyridazine 1-oxide (XII) was obtained preferentially. Treatment of I with acetyl anhydride at 138° for 3 hr gave 3-acetoxymethyl-6-methylpyridazine 1-oxide (XVII) and 3, 6-bis(acetoxymethyl)pyridazine (XVIII) in 4% and 2% yields, respectively.