Two palladiumcomplexes containing triene-coordinated ligands, 3 and 4, open-chain analogues of the macrocyclic palladium(0) complexes of type 1, have been synthesized. A comparative study of both open-chain and macrocyclic complexes has been carried out, based on a NMR and X-ray structural analysis, a DSC thermal behavior assessment, and a catalytical activity evaluation in the arenediazonium and