Abstract
Nitration of 3, 4-dimethyl (Ia), 6-chloro-3, 4-dimethyl (Ib), 6-methoxy-3, 4-dimethylpyridazine 2-oxide (Ic), 3, 4-dimethyl (Id) and 3-methylpyridazine 1-oxide (Ie) was examined and it was proved that Ia, Ib, Ic and Ie afforded γ-nitropyridazine N-oxides (IIa∼IIe), whereas Id in which γ-position was substituted gave α-nitro N-oxide (IId). All of these nitro derivatives were derived to aminopyridazines (IIIa∼IIIe) by catalytic reduction over Raney-nickel in methanol or over palladium-charcoal in dilute hydrochloric acid. Ultraviolet spectra of several aminopyridazines are also given.
