Platinum bis(acetylacetonate)
[CAS# 15170-57-7]

Identification

• Classification: Organic raw materials >> Organometallic compound >> Organic hafnium, mercury, silver, platinum, etc.
• Name: Platinum bis(acetylacetonate)
• Synonyms: Platinum(II)-2,4-pentanedionate; Bis(pentane-2,4-dionato-O,O')platinum
• Molecular Formula: C₁₀H₁₄O₄Pt
• Molecular Weight: 393.30
• CAS Registry Number: 15170-57-7
• EC Number: 239-223-5
• SMILES: CC(=O)C=C(C)O[Pt]OC(C)=C/C(C)=O

Properties

• Melting point: 250 - 252 °C (Expl.)
• Solubility: Very soluble (chloroform), insoluble (water)(Expl.)
• Sublimation: 170 °C

Safety Data

• Hazard Symbols: GHS07;GHS08 Warning
• Risk Statements: H302-H312-H315-H319-H332-H335-H361
• Safety Statements: P203-P261-P264-P264+P265-P270-P271-P280-P301+P317-P302+P352-P304+P340-P305+P351+P338-P317-P318-P319-P321-P330-P332+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Acute toxicity	Acute Tox.	4	H332
Acute toxicity	Acute Tox.	4	H312
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315
Reproductive toxicity	Repr.	2	H361
Specific target organ toxicity - single exposure	STOT SE	3	H335
Chronic hazardous to the aquatic environment	Aquatic Chronic	4	H413

Discovery and Applications

Platinum bis(acetylacetonate), commonly designated as Pt(acac)₂, is a coordination complex where a platinum(II) center is chelated by two acetylacetonate ligands. Each acetylacetonate (acac) ligand acts as a bidentate chelator through its oxygen atoms, forming stable five-membered rings with the central platinum ion. The complex typically appears as a yellow to orange crystalline solid, which is soluble in a variety of organic solvents including chloroform, benzene, and ethanol.

The synthesis of Pt(acac)₂ generally involves the reaction of platinum(II) salts, such as platinum(II) chloride, with acetylacetone in the presence of a base. The base deprotonates acetylacetone, enabling it to coordinate to platinum through enolate oxygen atoms. This reaction is typically carried out under reflux conditions in organic solvents. The resulting Pt(acac)₂ complex is isolated by filtration or crystallization and purified by recrystallization.

Structurally, Pt(acac)₂ adopts a square planar geometry around the platinum(II) ion, which is characteristic of d⁸ metal centers. The bidentate acac ligands coordinate via their two oxygen atoms, resulting in two planar chelate rings. This configuration confers stability to the complex due to the chelate effect and strong metal-ligand bonding.

Platinum bis(acetylacetonate) is extensively used as a precursor in both homogeneous and heterogeneous catalysis. It serves as a source of platinum in the synthesis of catalysts for hydrogenation, oxidation, and carbon-carbon coupling reactions. Due to its solubility and stability, Pt(acac)₂ facilitates the preparation of supported platinum catalysts by impregnation methods and is also used in the fabrication of platinum-containing materials through chemical vapor deposition and sol-gel techniques.

In organometallic chemistry, Pt(acac)₂ is employed as a starting material for the synthesis of more complex platinum compounds. Ligand substitution reactions can replace one or both acac ligands with phosphines, olefins, or nitrogen-based ligands to tune the electronic and steric properties of the platinum center. Such derivatives are valuable in mechanistic studies and as catalysts in various organic transformations.

The complex also finds applications in materials science, particularly in the preparation of platinum thin films and nanoparticles. These materials are used in electronics, sensors, and fuel cells due to their excellent electrical conductivity and catalytic properties. Pt(acac)₂ acts as a convenient molecular precursor for the deposition of platinum metal via thermal or photochemical decomposition.

From a safety perspective, platinum bis(acetylacetonate) should be handled with care. It is moderately toxic and may cause irritation upon contact with skin or eyes. Appropriate personal protective equipment is recommended when handling the compound. It should be stored in a cool, dry place away from strong oxidizing agents to maintain stability.

In summary, platinum bis(acetylacetonate) is a stable, square planar platinum(II) complex with two bidentate acetylacetonate ligands. It is widely used as a precursor in catalysis, materials synthesis, and organometallic chemistry, valued for its stability, solubility, and versatility in ligand substitution and catalytic applications.

References

2024. Synthesis of a Novel Platinum Catalyst and Its Application in the Photoactivated Hydrosilylation Reaction. Silicon, 16(7).
DOI: 10.1007/s12633-024-03103-8

2024. Regioselective epitaxial growth of metallic heterostructures. Nature Nanotechnology, 19(6).
DOI: 10.1038/s41565-024-01696-0

2023. H2O Promotion of CO Oxidation On Oxidized Pt/CeFeOx. Catalysis Letters, 153(10).
DOI: 10.1007/s10562-023-04480-2