Pyrazolones as Building Blocks in Heterocyclic Synthesis: Synthesis of New Pyrazolopyran, Pyrazolopyridazine and Pyrazole Derivatives of Expected Antifungicidal Activity

A series of new pyrazolone and pyrazole derivatives with expected antifungicidal activity have been prepared through the reactions 3‐phenyl‐1‐H‐pyrazol‐5(4H)‐one (3) and 4‐(dimethylaminomethylene)‐3‐phenyl‐1H‐pyrazol‐5(4H)‐one (5) with a variety of electrophilic reagents and nucleophilic reagents. The newly synthesized compounds were characterized by IR, 1H NMR, 13C NMR and mass spectral studies.