Heinisch, Gottfried published the artcilePyridazines. Part 13. Substitution of the 1,2-diazine system with sym-trioxanyl radicals; a route to pyridazinecarbaldehydes, COA of Formula: C5H4N2O, the publication is Journal of Heterocyclic Chemistry (1980), 17(7), 1501-4, database is CAplus.
Pyridazine and 3-methylpyridazine were selectively attacked by sym-trioxanyl radicals at C-4 and/or C-5, but 4-methylpyridazine reacts under similar conditions to give not only the C-5 substitution product but also 3- and/or 6-trioxanylsubstituted methylpyridazines. Some of the reaction products were hydrolyzed to the formylmethylpyridazines.
Journal of Heterocyclic Chemistry published new progress about 50901-42-3. 50901-42-3 belongs to pyridazine, auxiliary class Pyridazine,Aldehyde, name is Pyridazine-4-carbaldehyde, and the molecular formula is C5H4N2O, COA of Formula: C5H4N2O.
Referemce:
https://en.wikipedia.org/wiki/Pyridazine,
Pyridazine | C4H4N2 – PubChem