Structural alterations on copper cages containing hydrides coordinated to the central Pd(0)

A crucial component of nanocluster (NC) chemistry is the design and control of complex molecular architectures with atomic precision. Herein, we report the synthesis and structure of [PdH2Cu11{S2P(OiPr)2}6(CCPh)3] (PdH2Cu11), confirmed by single-crystal X-ray diffraction (SC-XRD), NMR spectroscopy, elemental analysis, and electrospray ionization mass spectrometry (ESI-MS). PdH2Cu11 is obtained from the reaction of a parent cluster [PdH2Cu14{S2P(OiPr)2}6(CCPh)6] (PdH2Cu14) with trifluoroacetic acid (TFA). Importantly the addition of TFA does not result in the loss of the hydride atoms located at the kernel, and H-Pd-H motif is retained. The molecular structure of PdH2Cu11 consists of a distorted 3,3,4,4,4-pentacapped trigonal prism Cu11 cage encapsulating a quasi-linear H-Pd-H unit, stabilized by dithiophosphate and alkynyl ligands. DFT calculations suggest an ionic inclusion complex of the type [{PdH2}2−]@[{Cu11{S2P(OiPr)2}6(CCPh)3}2+] and confirm the hydride positions. A non-covalent inter-cluster interaction results in the unique formation of a unique honeycomb crystal lattice. Overall, this work broadens and deepens the understanding of Pd-Cu hydride alloy nanoclusters.