Synthesis and properties of a redox active ligand with bispicorylamino groups and its dinuclear complex

A ligand, 4-methoxy-4′,4″-bis[N,N-bis(2-pyridylmethyl) aminomethyl]triphenyl-amine, and its palladium and copper dinuclear complexes were designed and prepared in order to examine intramolecular interactions between an organic cation radical and the metal ion. Novel NMR techniques, COSY and NOESY, were applied to the palladium complex to examine its conformation in solution. The palladium complex was found to prefer a folded conformation at ambient temperature, indicating the occurrence of intramolecular stacking interaction. CV measurements of the copper complex showed reversible Cu^I/Cu^II and TPA/TPA⁺ redox couples. The spin–spin interaction in the radical pendant copper complex generated upon one electron oxidation of the copper complex was examined by cw-ESR measurements.