Acetone, dibenzylidene palladium complex

Reactions carried out with M2(DBA)3 (M — Pd, Pt DBA = dibenzylidene-acetone) and 3,5-di-t-butyl-l,2-benzquinone gave as major products the M(DBSQ)2 complexes [229]. In the case of palladium, an additional product Pd2[Pd(DBSQ)2]2 was detected, whose molecular structure consists of two planar cw-Pd(DBSQ)2 units bridged by two Pd atoms. The Pd atoms are sandwiched between semiquinone rings of adjacent Pd(DBSQ)2 units with three Pd — C lengths and an allyl structure 961 for the semiquinone rings ... 

There are many available complexes of palladium(O) and pal ladiumfl I). T etrak is tri ph e ny I ph osph i ne)pal I ad iu m (0). Pd PPh3)4, and tris dibenzylidene-acetone)dipalladium 0), Pd2 dba)3, or the chloroform complex, Pd2(dba)3-CHCI3 which is air-stable, are the most common sources of... 

In some cases, reasonably stable palladium(O) complexes derived from dibenzylidene-acetone [such as Pd(dba)2, Pd2(dba)3, or Pd2(dba)3-CHCl3] can be utilized advantageously, especially when the substrate is sensitive toward oxidation. 

The palladium(0) complexes [e.g., Pd(PPh3)4 and [Pd(dba)2 (dba=dibenzylidene-acetone)] are formed by reduction of the palladium(II) analog. Alkyne, alkene, and nitroso derivatives are also known, the more stable palladium(O) complexes being formed with ligands having strong r-acceptor ability. 

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