Abstract
Treatment of 3, 6-dimethoxypyridazine 1-oxide (I) with phosphoryl chloride at room temperatrue gave a chloro-dimethoxyl compound (II), m.p. 86°, and reaction of (II) with sodium methoxide yielded a trimethoxyl compound (III), which was proved to be identical with 3, 4, 6-trimethoxypyridazine. This shows that, when ortho position of the N-oxide group in pyridazine N-oxides is substituted, the reaction with phoshoryl chloride seems to give a chloro compound which has chlorine atom at a position para to the N-oxide group.
