Tris(dibenzylideneacetone)dipalladium
[CAS# 51364-51-3]

Identification

• Classification: Organic raw materials >> Organometallic compound >> Organic palladium
• Name: Tris(dibenzylideneacetone)dipalladium
• Synonyms: Bis(dibenzylideneacetone)palladium
• Molecular Formula: C₅₁H₄₂O₃Pd₂
• Molecular Weight: 915.73
• CAS Registry Number: 51364-51-3 (52409-22-0 / 60748-47-2)
• EC Number: 610-654-4
• SMILES: C1=CC=C(C=C1)/C=C/C(=O)/C=C/C2=CC=CC=C2.C1=CC=C(C=C1)/C=C/C(=O)/C=C/C2=CC=CC=C2.C1=CC=C(C=C1)/C=C/C(=O)/C=C/C2=CC=CC=C2.[Pd].[Pd]

Properties

• Melting point: 152-155 °C
• Water solubility: insoluble

Safety Data

• Hazard Symbols: GHS02;GHS07 Danger
• Risk Statements: H228-H302-H312-H315-H319-H332
• Safety Statements: P210-P240-P241-P261-P264-P264+P265-P270-P271-P280-P301+P317-P302+P352-P304+P340-P305+P351+P338-P317-P321-P330-P332+P317-P337+P317-P362+P364-P370+P378-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin sensitization	Skin Sens.	1	H317
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Skin irritation	Skin Irrit.	2	H315
Specific target organ toxicity - single exposure	STOT SE	3	H335
Eye irritation	Eye Irrit.	2	H319
Flammable solids	Flam. Sol.	1	H228
Flammable solids	Flam. Sol.	2	H228
Eye irritation	Eye Irrit.	2A	H319
Acute toxicity	Acute Tox.	4	H312
Serious eye damage	Eye Dam.	1	H318
Acute toxicity	Acute Tox.	4	H332
Acute toxicity	Acute Tox.	4	H302

Discovery and Applications

Tris(dibenzylideneacetone)dipalladium, commonly known as Pd2(dba)3, is a well-known and widely used organopalladium complex in synthetic chemistry. It consists of two palladium atoms coordinated by three dibenzylideneacetone (dba) ligands, each of which acts as a bidentate ligand. The complex is of significant interest due to its utility in various catalytic reactions, particularly in organic synthesis.

The discovery and development of Pd2(dba)3 are tied to the broader field of organometallic chemistry and catalysis. The compound was first reported in the literature in the 1970s as a highly active catalyst precursor for a variety of reactions, especially in the context of palladium-catalyzed cross-coupling reactions. These reactions have become fundamental tools in organic synthesis, enabling the formation of carbon-carbon bonds in a highly efficient manner.

The primary application of Pd2(dba)3 is as a catalyst precursor for the Heck reaction, a key palladium-catalyzed transformation where aryl halides react with alkenes to form substituted alkenes. The complex is highly effective in this reaction due to its ability to undergo oxidative addition, which forms the active palladium species that then participates in the catalytic cycle. This reaction is essential for the synthesis of a wide variety of important compounds, including pharmaceuticals, agrochemicals, and advanced materials.

Pd2(dba)3 is also a crucial catalyst precursor for other cross-coupling reactions, such as the Suzuki and Stille reactions. In the Suzuki coupling, palladium-catalyzed coupling of aryl boronic acids with aryl or vinyl halides produces biaryl compounds, which are vital intermediates in medicinal chemistry and materials science. The Stille reaction, similarly, involves the coupling of organotin reagents with halides, providing another versatile method for the synthesis of complex organic molecules.

Beyond its role in cross-coupling reactions, Pd2(dba)3 has been used in a variety of other transformations, including the direct arylation of heteroarenes, coupling of alkynes with halides, and other carbon-carbon bond-forming reactions. Its stability and ease of handling make it a preferred catalyst precursor in both laboratory and industrial settings.

One of the advantages of Pd2(dba)3 is its ability to form stable palladium complexes under mild conditions. The dibenzylideneacetone ligands are known to provide excellent stability to the palladium center, which allows the catalyst to be used in a variety of solvents and reaction conditions. Additionally, the ligands play a role in controlling the electronic properties of the palladium center, which can influence the reactivity and selectivity of the catalyst in different reactions.

In conclusion, Tris(dibenzylideneacetone)dipalladium (Pd2(dba)3) is a well-established and highly versatile catalyst precursor in the field of organic synthesis. Its primary applications lie in palladium-catalyzed cross-coupling reactions, including the Heck, Suzuki, and Stille reactions, where it facilitates the formation of carbon-carbon bonds. The compound has proven to be a reliable and efficient tool for chemists, enabling the synthesis of a wide range of organic compounds, including complex pharmaceuticals and materials. Its stability, ease of handling, and ability to catalyze various reactions make it an indispensable reagent in modern synthetic chemistry.

References

(2025). Palladium-catalysed [2σ + 2π] cycloaddition reactions of bicyclo[1.1.0]butanes with aldehydes. Nature Synthesis, 4.
DOI: https://doi.org/10.1038/s44160-024-00659-6

(2025). Pyrazine-fused polycyclic aromatic hydrocarbons towards efficient multiple-resonance narrowband deep-blue emission. Science China Chemistry, 68.
DOI: https://doi.org/10.1007/s11426-024-2264-7

(2024). Vinylic-addition Polynorbornene-based Anion-Exchange Membranes with Semi-Interpenetrating Polymer Networks for Water Electrolysis. Chinese Journal of Polymer Science, 42.
DOI: https://doi.org/10.1007/s10118-024-3225-2