Tris(dibenzylideneacetone)dipalladium(0) or d₂(dba)₃is an organopalladium compound. The compound is a complex of

palladium Palladium is a chemical element with the symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by the English chemist William Hyde Wollaston. He named it after the asteroid Pallas, which was itself nam ...

(0) with dibenzylideneacetone (dba). It is a dark-purple/brown solid, which is modestly soluble in organic solvents. Because the dba ligands are easily displaced, the complex is used as a

homogeneous catalyst In chemistry, homogeneous catalysis is catalysis by a soluble catalyst in a solution. Homogeneous catalysis refers to reactions where the catalyst is in the same phase as the reactants, principally in solution. In contrast, heterogeneous catalysis ...

organic synthesis Organic synthesis is a special branch of chemical synthesis and is concerned with the intentional construction of organic compounds. Organic molecules are often more complex than inorganic compounds, and their synthesis has developed into one o ...

Preparation and structure

Tris(dibenzylideneacetone)dipalladium(0)

First reported in 1970, it is prepared from dibenzylideneacetone and

sodium tetrachloropalladate Sodium tetrachloropalladate is an inorganic compound with the chemical formula Na2PdCl4. This salt, and the analogous alkali metal salts of the form M2PdCl4, may be prepared simply by reacting palladium(II) chloride with the appropriate alkali meta ...

. Because it is commonly recrystallized from chloroform, the complex is often supplied as the adduct d₂(dba)₃·CHCl₃Jiro Tsuji and Ian J. S. Fairlamb "Tris(dibenzylideneacetone)dipalladium–Chloroform" E-EROS, 2008. The purity of samples can be variable. In d₂(dba)₃ the pair of Pd atoms are separated by 320 pm but are tied together by dba units. The Pd(0) centres are bound to the alkene parts of the dba

ligand In coordination chemistry, a ligand is an ion or molecule ( functional group) that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's ele ...

Applications

d₂(dba)₃is used as a source of soluble Pd(0), in particular as a

catalyst Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...

for various coupling reactions. Examples of reactions using this reagent are the Negishi coupling,

Suzuki coupling The Suzuki reaction is an organic reaction, classified as a cross-coupling reaction, where the coupling partners are a boronic acid and an organohalide and the catalyst is a palladium(0) complex. It was first published in 1979 by Akira Suzuki, ...

Carroll rearrangement The Carroll rearrangement is a rearrangement reaction in organic chemistry and involves the transformation of a β- keto allyl ester into a α-allyl-β-ketocarboxylic acid. This organic reaction is accompanied by decarboxylation and the final produc ...

, and

Trost asymmetric allylic alkylation Trost may refer to: People * Al Trost, United States soccer midfielder * Barry Trost, American chemist * Brad Trost, Canadian Member of Parliament * Carlisle Trost, United States Navy officer * Dolfi Trost, Romanian surrealist * Katharina Trost, G ...

, as well as

Buchwald–Hartwig amination In organic chemistry, the Buchwald–Hartwig amination is a chemical reaction for the synthesis of carbon–nitrogen bonds via the palladium-catalyzed coupling reactions of amines with aryl halides. Although Pd-catalyzed C-N couplings were repo ...

. Related Pd(0) complexes are d(dba)₂ref>John R. Stille, F. Christopher Pigge, Christopher S. Regens, Ke Chen, Adrian Ortiz and Martin D. Eastgate "Bis(dibenzylideneacetone)palladium(0)" E-eros. 2013. and tetrakis(triphenylphosphine)palladium(0).

References

{{Palladium compounds Catalysts Organopalladium compounds