Structure, Spectral Properties, and Complexing Ability of 1-Phenyl-3-methylpyrazol-5-one Ferrocenoyl Hydrazone

A potentially tridentate coordinating chelating ligand system, 1-phenyl-3-methylpyrazol-5-one ferrocenoylhydrazone, has been synthesized. Structure of the obtained ligand and its equilibrium forms in the solution has been elucidated from the data of elemental analysis, IR, electronic absorption and NMR ( 1 H, 13 C, and 15 N NMR including 1 H– 1 H COSY, 1 H– 1 H NOESY, 1 H– 13 C HSQC, 1 H– 13 C HMBC, and 1 H– 15 N HMBC 2D correlation techniques) spectroscopy as well as quantum chemistry methods. The reactions of 1-phenyl-3-methylpyrazol-5-one ferrocenoylhydrazone with selected transition metal ions have afforded metal chelates, their composition, the mode of coordination, and type of tautomeric form of the coordinated ligand being dependent on the metal nature.