ChemInform Abstract: Novel Synthesis of 1,4-Phenylene Bridged Bis-heterocyclic Tropone Compounds

Nucleophilic cyclization reaction of bis(tropolone) derivative (III), which is obtained by Claisen-Schmidt condensation between terephthalaldehyde (I) and acetyltropolone (II), with bifunctional agents such as substituted phenylhydrazine hydrochlorides (IV) and hydroxylamine hydrochloride gives rise to formation of the desired 1,4-phenylene bridged bis-pyrazolo and isoxazole-fused tropones (V) and (VI).