Two oxo complexes with tetranuclear [Fe(4)(mu(3)-O)(2)](8+) and trinuclear [Fe(3)(mu(3)-O)](7+) units
Piedad Cortés1, Ana María Atria, María Teresa Garland
1Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile. pcortes@ciq.uchile.cl
Summary
Two novel iron oxo complexes, one tetranuclear and one trinuclear, exhibit distinct structural and charge characteristics. These findings advance the understanding of complex iron cluster chemistry and crystal engineering.
Area of Science:
- Coordination Chemistry
- Inorganic Chemistry
- Crystal Engineering
Background:
- Iron oxo clusters are crucial in various biological and catalytic processes.
- Understanding the structural diversity and charge distribution in iron complexes is key to designing new materials.
- Previous research has explored polynuclear iron clusters, but novel structural motifs and charge balancing mechanisms are continually sought.
Purpose of the Study:
- To synthesize and characterize two new iron oxo complexes with distinct nuclearities (tetranuclear and trinuclear).
- To elucidate the detailed crystal structures and supramolecular arrangements of these complexes.
- To investigate the charge distribution and bonding interactions within the crystal lattices.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the molecular and crystal structures of the synthesized complexes.
- Spectroscopic and analytical techniques were used for characterization and confirmation of the proposed structures.
- Analysis of crystallographic data to understand charge balance and hydrogen bonding networks.
Main Results:
- Synthesis and structural determination of hexa-mu(2)-acetato-acetatoaquabis(di-3-pyridylamine)di-mu(3)-oxo-tetrairon(III) chloride monohydrate ethanol 1.25-solvate ([Fe(4)(C(2)H(3)O(2))(7)O(2)(C(10)H(9)N(3))(2)(H(2)O)]Clx1.25C(2)H(6)OxH(2)O) featuring a tetranuclear [Fe(4)(mu(3)-O)(2)](8+) core.
- Synthesis and structural determination of 2-methylimidazolium hexa-mu(2)-acetato-acetatodiaqua-mu(3)-oxo-triiron(III) chloride dihydrate ((C(4)H(7)N(2))[Fe(3)(C(2)H(3)O(2))(7)O(H(2)O)(2)]Clx2H(2)O) with a trinuclear [Fe(3)(mu(3)-O)](7+) core.
- Both structures consist of isolated metal clusters and external chloride/solvent groups, with complex (I) showing macroscopic ionic character and complex (II) exhibiting local charge neutrality within its constituent groups.
Conclusions:
- The study presents two novel iron oxo complexes with unique tetranuclear and trinuclear metal cores.
- The structural analysis reveals distinct charge distribution patterns, highlighting different modes of charge compensation in related polynuclear iron complexes.
- These findings contribute to the understanding of self-assembly in coordination compounds and provide insights into the formation of complex supramolecular architectures.
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