Hexa(acetato)m3-oxo-tris(aquo)triiridium acetate
[CAS# 52705-52-9]

Identification

• Classification: Organic raw materials >> Organometallic compound >> Organic germanium, cobalt, strontium, barium, gallium, germanium, germanium, germanium, germanium, etc.
• Name: Hexa(acetato)m3-oxo-tris(aquo)triiridium acetate
• Synonyms: Iridium(III) acetate
• Molecular Formula: C₁₂H₁₈Ir₃O₁₅^.C₂H₃O₂^.3(H₂O)
• Molecular Weight: 1092.00
• CAS Registry Number: 52705-52-9
• EC Number: 679-513-2
• SMILES: CC(=O)O[Ir]1(OC(C)=O)O[Ir](OC(C)=O)(OC(C)=O)O[Ir+](OC(C)=O)(OC(C)=O)O1.CC(=O)[O-].O.O.O

Safety Data

• Hazard Symbols: GHS07 Danger
• Hazard Statements: H290-H302-H318
• Precautionary Statements: P234-P264-P270-P280-P301+P312-P305+P351+P338-P330-P337+P313-P390-P406-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Substances or mixtures corrosive to metals	Met. Corr.	1	H290
Acute toxicity	Acute Tox.	4	H302
Eye irritation	Eye Irrit.	2	H319

• Transport Information: UN 1759

Discovory and Applicatios

Hexa(acetato)m³-oxo-tris(aquo)triiridium acetate is a well-characterized multinuclear iridium complex featuring three iridium centers bridged by an oxo ligand and coordinated by acetate and water ligands. Its molecular structure includes three iridium atoms connected via a μ₃-oxo bridge (an oxygen atom simultaneously bonded to all three metal centers), six acetate groups acting as bridging and terminal ligands, and three coordinated water molecules. Additionally, acetate anions are present as counterions, balancing the overall charge of the complex.

This compound belongs to a class of polynuclear metal-oxo clusters that have attracted attention for their unique structural, electronic, and catalytic properties. The trinuclear iridium cluster exhibits an octahedral coordination geometry around each iridium center, stabilized by bridging acetate ligands and the central μ₃-oxo group. The μ₃-oxo ligand plays a crucial role in linking the three metal centers, facilitating metal-metal electronic communication and structural integrity.

The synthesis of hexa(acetato)m³-oxo-tris(aquo)triiridium acetate typically involves the reaction of iridium(III) chloride or iridium trichloride hydrate with sodium acetate in aqueous or alcoholic media. Under controlled pH and temperature conditions, the hydrolysis of iridium salts occurs, and the formation of the μ₃-oxo-bridged trinuclear core is promoted. The acetate ions serve both as ligands and as base to neutralize acidic byproducts, facilitating the assembly of the cluster. Purification methods include crystallization and filtration, often yielding the compound as a crystalline solid.

This iridium cluster is extensively studied for its catalytic applications, particularly in oxidation reactions. The multinuclear nature and the presence of the oxo bridge provide redox-active sites capable of facilitating electron transfer processes. Such complexes have been used as catalysts or catalyst precursors in reactions such as water oxidation, alkane hydroxylation, and other oxidation processes relevant to both industrial and environmental chemistry.

The compound’s stability and well-defined structure make it a valuable model system for investigating the electronic properties of metal-oxo clusters. Spectroscopic techniques including ultraviolet-visible (UV-Vis) absorption spectroscopy, infrared (IR) spectroscopy, and nuclear magnetic resonance (NMR) are commonly employed to characterize the complex. UV-Vis spectra typically exhibit bands related to metal-to-ligand charge transfer and d–d transitions, while IR spectroscopy confirms the presence of acetate ligands (via characteristic C=O stretching frequencies) and the μ₃-oxo bridge (with an intense M–O stretching band). X-ray crystallography has provided detailed information on bond lengths, coordination geometry, and metal-metal distances, confirming the trinuclear oxo-bridged structure.

The aqueous solubility of hexa(acetato)m³-oxo-tris(aquo)triiridium acetate and its stability under various conditions allow for its use in homogeneous catalytic systems. Its redox properties are of particular interest for electrochemical applications, including water-splitting catalysis, where the efficient generation of oxygen from water is a key challenge.

In summary, hexa(acetato)m³-oxo-tris(aquo)triiridium acetate is a trinuclear iridium complex characterized by a central μ₃-oxo bridge, coordinated acetate ligands, and water molecules. It serves as an important compound in organometallic and coordination chemistry with applications mainly in catalysis, especially oxidation reactions, due to its unique multinuclear and redox-active structure.