Palladium(II) complexes / Oligonitriles / N ligands / S ligands / N-Acylimine Two mononuclear six-membered chelate PdCl 2 complexes donor-acceptor interactions involving the terminal amino group and the N3-Pd moiety of the molecule. The complex 2a, b of the two different types of tetrameric oligonitriles 1a, b have been synthesized. Both contain square-planar 2b is derived from the thiobenzoyl ligand 1b bearing a
terminal (R)-fenchylidene group. In 2b the sulfur atom S1 palladium(II) with a cis arrangement of the chloride atoms. In complex 2a of the ω-amino-substituted N-methoxycarbonyl and the nitrogen atom N2 are involved in complexation. In contrast to 2a, strong bond-length alternation is observed in oligonitrile 1a the metal center is coordinated by the nitrogen atoms N1 and N3. Within the chelate ring alternating bond 2b for the complexed and the non-complexed part of the ligand. From the NMR spectra of both complexes no lengths for the C-N bonds are observed, whereas the noncomplexed, more flattened part of the oligonitrile chain indication for a migration of the PdCl 2 unit along the chain could be derived. shows almost equal C-N bond lengths, indicating strong [ ] Part VII: ref. ladium compound, coordination to nitrogen atoms is [a] Institute of Organic Chemistry, Westfälische Wilhelms-Universiclearly preferred over complexation to oxygen atoms of the tät, methoxycarbonyl group. The chelate ring deviates strongly Corrensstraße 40, D-48149 Münster, Germany Fax: (internat.) ϩ 49(0)251/83-39772 from planarity leading to a twisted-boat-shaped structure.