Studies with 3-functionally substituted 2-arylhydrazononitriles: A new route to 3-substituted-2-arylhydrazononitriles, 4-amino-pyrazole-5-carbonitriles, azadienes and cinnolines

3-Amino-3-phenyl-2-phenylazoacrylonitrile 6 is obtained in good yield via reaction of 5 with phenyl magnesium bromide. The compound 6 is readily converted into 4a. The so formed alkanenitrile reacted with phenylmagnesium bromide to yield 8. Compound 8 could be also obtained from reaction of 9 with phenylmagnesium bromide. The arylhydrazononitriles 8 and 4a reacted with chloroacetonittile to yield the 4-aminopyrazoles 12a,b. Compound 12a reacted with acetic anhydride to yield the 15a and with benzoyl chloride to yield the pyrazole 16 which was converted into 15b. Refluxing 10 in acetic acid gave a mixture of the azadiene 21 and the cinnoline 22 is obtained. The azadiene 21 is converted into 22 either thermally or photochemically.