Conversion into Arylazo-or Azidophthalazines

Only AT-arylhydrazinophthalazines may be oxidized to the corresponding arylazophthalazines, and only (unsubstituted-hydrazino)phthalazines react with nitrous acid to give azidophthalazines. These reactions are illustrated by the following examples. 

These seldom used reactions are illustrated by the following classified examples. 

4-Hydrazino-2-phenyl-l(2//)-phthalazinone (109, R = H) gave 4-[A/ -(chloroa-cetyl)hydrazino] - 2-phenyl-1 (2fl)-phthalazinone [109, R = C(=0)CH2C1] (CICH2COCI, PhH 70%, no other details).  

4-Dihydrazinophthalazine likewise gave l,4-bis[4-methyl(thiosemicarbazi-do)]phthalazine (114) (MeNCS).  

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