Reactions with 3-pyrazolin-5-ones: synthesis of some 4-substituted 2,3-dimethyl-1-phenyl-3-pyrazolin-5-ones

Article abstract of DOI:10.1002/ardp.19833160115

4-Acetylantipyrine (1) was condensed with aromatic or heterocyclic aldehydes to yield the cinnamoylidene derivatives 4a-d. Compound 4b was converted into the pyrazolinylantipyrine derivative 9 by hydrazine hydrate. 4-(Chloroacetyl)antipyrine (2) reacted w