Structure and Properties of Lantern‐Shaped Hexapalladium Complexes with Germylene and Thiolate Ligands [Pd₆(µ‐GePh₂)₂(µ‐SC₆H₄‐p‐X)₂(CN‐C₆H₃Me₂‐2,6)₈] (X = NO₂, Cl, H, CH₃)

Abstract

Reaction of diaryl disulfides, ArSSAr (Ar = C6H4‐p‐Cl, Ph, C6H4‐p‐CH3) with a hexapalladium complex with bridging germylene ligands, [Pd6(µ‐GePh2)2(CN‐C6H3Me2‐2,6)8(µ‐CN‐C6H3Me2‐2,6)2] (1) afforded arylthiolate‐bridged complexes, [Pd6(µ‐GePh2)2(µ‐SAr)2(CN‐C6H3Me2‐2,6)8] (Ar = C6H4‐p‐Cl, Ph, C6H4‐p‐CH3) (3–5). The Pd(0)4Pd(I)2 complexes as well as analogous complex with 4‐nitrophenylthiolate ligands [Pd6(µ‐GePh2)2(µ‐SC6H4‐p‐NO2)2(CN‐C6H3Me2‐2,6)8] (2) have a hexagonal bipyramidal structure which contains two bridging thiolate ligands at basal coordination sites. Electrochemical measurement of 2–5 showed one reversible redox wave at E1/2 = –0.51 (2), –0.61 (3), –0.66 (4) and –0.70 (5) V (vs. Fc+/Fc) in the oxidation region, and irreversible reduction peak at Epc = –2.04 (2), –2.29 (3), and –2.38 (4) V (vs. Fc+/Fc) in the reduction region. Both oxidation and reduction potentials are correlated well with Hammett substitution constant σp of the aryl group of the thiolate ligands.

Discrete palladium clusters that consist of two mutually bisecting perpendicular planes

“…0.1 Å shorter than those found in sheet I and II in 2 . The synthesis of hexanuclear palladium clusters that include a similar hexagonal Pd 4 Ge 2 subunit, consisting of four palladium and two germylene moieties, has already been reported by Osakada et al 20 However, the Pd 4 Ge 2 planes in that cluster adopt a distorted planar structure, wherein the four palladium atoms deviate from the Pd 4 Ge 2 plane by ca. 0.05–0.29 Å.…”