Iron(III) complexes with a biologically relevant aroylhydrazone: crystallographic evidence for coordination...

Area of Science:

• Coordination Chemistry
• Inorganic Chemistry
• Supramolecular Chemistry

Background:

• Iron complexes are crucial in various chemical and biological processes.
• Heterodonor chelating agents offer diverse coordination possibilities.
• Aroylhydrazone ligands are known for their chelating abilities.

Purpose of the Study:

• To investigate the complexation behavior of iron(III) with a specific benzoylhydrazine derivative.
• To explore the coordination versatility of 3,5-di-tert-butylsalicylidene benzoylhydrazine (H2(3,5-tBu2)salbh) with iron.
• To characterize the resulting iron complexes structurally and spectroscopically.

Main Methods:

• Synthesis of iron(III) complexes with H2(3,5-tBu2)salbh in the absence and presence of a base.
• Single-crystal X-ray diffraction analysis to determine the solid-state structures.
• Magnetic measurements and spectroscopic techniques (e.g., UV-Vis, IR) to verify oxidation and spin states.

Main Results:

• Formation of a complex cation [Fe{H(3,5-tBu2)salbh}2]+ in the absence of a base.
• Formation of a neutral compound [Fe{H(3,5-tBu2)salbh}{(3,5-tBu2)salbh}] in the presence of a base.
• Crystallographic data confirmed the distinct coordination modes and structures.
• Magnetic and spectroscopic data corroborated the assigned iron oxidation and spin states.

Conclusions:

• The benzoylhydrazine ligand exhibits significant coordination versatility with iron(III).
• The reaction conditions (presence or absence of base) dictate the final complex structure.
• This study provides a rare synthetic and crystallographic insight into aroylhydrazone coordination with iron.