The reaction of thiosemicarbazones 4-MeC 6 H 4 C(Me)᎐ ᎐ NN(H)C(᎐ ᎐ S)NH 2 a, C 6 H 5 C(Et)᎐ ᎐ NN(H)C(᎐ ᎐ S)NH 2 b and 4-MeC 6 H 4 C(Me)᎐ ᎐ NN(H)C(᎐ ᎐ S)NHMe c with K 2 [PdCl 4 ] led to tetranuclear palladiumthe ligands are tridentate through the [C, N, S ] atoms and they are deprotonated at the NH group. The Pd-S chelating bond is sufficiently strong for the complexes to undergo reactions with nucleophiles without bond cleavage. The molecular structure of 1b has been determined by single-crystal diffraction, confirming the formation of the tetranuclear moieties. Hydrogen bonding N ؒ ؒ ؒ H and S ؒ ؒ ؒ H links Pd 4 clusters into strands in the solid state. Reaction of 1a and 1b with phosphines gave mono-and di-nuclear species, 2a, 2b, 3b and 5a, 5b, respectively. Treatment with 1,1Ј-bis(diphenylphosphino)ferrocene led to trimetallic compounds 6a and 6b. The molecular structure of 3b has been determined by X-ray crystallography; dimer units are present through N ؒ ؒ ؒ H hydrogen bonds. The reaction of 2b with hydrochloric acid resulted in a 1 : 1 electrolyte, 4b, with NH and C᎐ ᎐ S groups. Alternatively, treatment of 1a, 1b and 1c with strong chelating phosphines produced mononuclear compounds with only cleavage of the Pd-S bridging bonds, 7a, 7b, 7c and 8c with the diphosphine monodentate; 7a and 7b were obtained with the dinuclear species 7aЈ and 7bЈ, respectively, as impurities, where the bidentate phosphine ligand bridges two metallated units. The crystal structure of one such compound, 7bЈ, with a bridging bis(diphenylphosphino)methane ligand, is also described.

The complexes [{(X) PdN(Cy) 2)) with 1,1′-bis(diphenylphosphino)ferrocene (dppf), and they were characterized by elemental analysis (C, H, N) and by 1 H and 31 P{ 1 H} NMR spectroscopy in CDCl 3 . The compounds are arranged as hexanuclear supramolecular cages containing two different metals, palladium and iron. The crystal structure of complex 4 was determined by X-ray diffraction studies.

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