From 6-Oxo-l,4,5,6-tetrahydropyridazines

For example, mixing 6-oxo-3-styryl-l,4,5,6-tetrahydropyridazine with a three- to fourfold molar excess of certain aryl and a-naphthylmagne-sium bromides has been reported to yield the 4,5-dihydropyridazine 68 

It was claimed that reaction of phenylmagnesium bromide with l-phenyl-6-oxodihydropyridazines affords 1,6-dihydropyridazines (69) [Eq. (15)].125 

Aubagnac et al. reported the isolation of 1,4-dihydropyridazines 70 among the products of the reduction of 6-oxo-l,4,5,6-tetrahydropyridazines with LiAlH4[Eq. (16)].126 

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