Synthesis,spectral characterization,electrochemical studies and catalytic properties in Suzuki–Miyaura coupling reactions of the mononuclear PdII,trinuclear PdII(BPh2)2 and RuII?PdII?RuII type complexes containing 4‐amino‐1‐benzyl piperidine and phenyl groups

The ligand containing the 4‐amino‐1‐benzyl piperidine group, N, N′‐(4‐amino‐1‐benzyl piperidine)‐glyoxime, (LH₂) (1) was prepared from 4‐amino‐1‐benzyl piperidine with anti‐dichloroglyoxime at ? 15 °C in absolute Tetrahydrofuran (THF). In the trinuclear Pd(L)₂Ru₂(phen)₄](ClO₄)₂ (4) and Pd(L)₂Ru₂(bpy)₄](ClO₄)₂ (5) metal complexes, the Pd^II ion centered into the main oxime core by the coordination of the imino groups while the two Ru^II ions coordinated dianionic oxygen donors of the oxime groups and linked to the ligands of 1,10‐phenanthroline and 2,2′‐bipyridine. The mono and trinuclear metal complexes were characterized by elemental analyses, FT‐IR, UV–vis, ¹H and ¹³C‐NMR spectra, magnetic susceptibility measurements, molar conductivity, cyclic voltammetry, mass spectra, X‐ray powder techniques and their morphology by SEM measurements. The cyclic voltammetric results show that the cathodic peak (E_pc) potential of (3) shifts towards more positive values compared with that of (2) as a result of the BPh₂⁺‐bridged complex formation. The Suzuki–Miyaura reaction was used to investigate their activity as catalyst either prepared in‐situ or from well‐defined complexes. Copyright © 2008 John Wiley & Sons, Ltd.