Discovery and Supramolecular Interactions of Neutral Palladium‐Oxo Clusters Pd₁₆and Pd₂₄

Abstract

We report on the synthesis, structure, and physicochemical characterization of the first three examples of neutral palladium-oxo clusters (POCs). The 16-palladium(II)-oxo cluster [Pd₁₆ O₂₄ (OH)₈ ((CH₃ )₂ As)₈ ] (Pd₁₆ ) comprises a cyclic palladium-oxo unit capped by eight dimethylarsinate groups. The chloro-derivative [Pd₁₆ Na₂ O₂₆ (OH)₃ Cl₃ ((CH₃ )₂ As)₈ ] (Pd₁₆ Cl) was also prepared, which forms a highly stable 3D supramolecular lattice via strong intermolecular interactions. The 24-palladium(II)-oxo cluster [Pd₂₄ O₄₄ (OH)₈ ((CH₃ )₂ As)₁₆ ] (Pd₂₄ ) can be considered as a bicapped derivative of Pd₁₆ with a tetra-palladium-oxo unit grafted on either side. The three compounds were fully characterized 1) in the solid state by single-crystal and powder XRD, IR, TGA, and solid-state ¹ H and ¹³ C NMR spectroscopy, 2) in solution by ¹ H, ¹³ C NMR and ¹ H DOSY spectroscopic methods, and 3) in the gas phase by electrospray ionization mass spectrometry (ESI-MS).