[Pd{2-CH2-5-MeC6H3C(H)NNC(S)NHEt}]3: An unprecedented trinuclear cyclometallated palladium(II) cluster through induced flexibility in the metallated ring

The reaction of 1-(2,5-dimethylbenzylidene)-3-ethylthiosemicarbazone and palladium acetate in acetic acid yields a trinuclear cyclometallated palladium(II) compound. Each thiosemicarbazone ligand is tridentate with the metal bonded to the carbon atom from the 2-methyl group, to the azomethine nitrogen and to the sulfur atom, which bridges to an adjacent palladium center. The crystal structure confirms the presence of a non-planar hexagonal metallated ring plus a central six-membered palladium–sulfur core within the trimer, which also displays a rather deep intramolecular cavity.

Graphical abstractThe trinuclear cyclometalated palladium(II) compound (2), with σ carbon(sp3)-metal bonding, contains a non-planar hexagonal metallated ring plus a central six-membered core of alternating palladium and sulfur atoms.Figure optionsDownload full-size imageDownload as PowerPoint slide