Tris(dibenzylideneacetone)dipalladium(0) or [Pd2(dba)3] is an organopalladium compound. The compound is a complex of palladium(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 organic synthesis.[1]
First reported in 1970,[2] it is prepared from dibenzylideneacetone and sodium tetrachloropalladate. Because it is commonly recrystallized from chloroform, the complex is often supplied as the adduct [Pd2(dba)3·CHCl3].[1] The purity of samples can be variable.[3]
In [Pd2(dba)3], the pair of Pd atoms are separated by 320 pm but are tied together by dba units.[4] The Pd(0) centres are bound to the alkene parts of the dba ligands.
[Pd2(dba)3] is used as a source of soluble Pd(0), in particular as a catalyst for various coupling reactions. Examples of reactions using this reagent are the Negishi coupling, Suzuki coupling, Carroll rearrangement, and Trost asymmetric allylic alkylation, as well as Buchwald–Hartwig amination.[5]
Related Pd(0) complexes are [Pd(dba)2][6] and tetrakis(triphenylphosphine)palladium(0).