Homoleptic Tetrakis(silyl) Complexes of Pd 0 and Pt 0 Featuring Metal‐Centred Heterocubane Structures: Evidence for the Existence of the Corresponding Mononuclear Pd I and Pt I Complexes

We report on the first homoleptic tetrakis(silyl) complexes of zerovalent Group 10 metals. The compounds [MLi 4 {Si(3,5‐Me 2 pz) 3 } 4 ] (M=Pd and Pt; 3,5‐Me 2 pz=3,5‐dimethylpyrazolyl) exhibit very appealing metal‐centred heterocubane structures with the central d 10 metal atoms surrounded by four silicon and four lithium atoms. Both compounds were characterised in detail, including X‐ray crystal‐structure analysis and 2D NMR spectroscopic methods such as 7 Li, 29 Si and 7 Li, 195 Pt HMQC. Cyclic voltammetry studies, in combination with density functional theory (DFT) calculations, revealed that the corresponding mononuclear cationic d 9 ‐M I and dicationic d 8 ‐M II complexes are accessible by stepwise one‐electron oxidation of the title compounds. Electron paramagnetic resonance (EPR) investigations provided evidence for the existence of the corresponding paramagnetic palladium(I) and platinum(I) complexes.