The oxidation chemistry of the complexes [{CpMo(CO) } (μ,η :η -E )] (E=P (A), As (B), Sb (C), Bi (D)) is compared. The oxidation of A-D with [Thia] (=[C H S ] ) results in the selective formation of the dicationic E complexes [{CpMo(CO) } (μ ,η :η :η :η -E )] (E=P (1), As (2), Sb (3), Bi (4)), stabilized by four [CpMo(CO) ] fragments. The formation of the corresponding monocations [A] , [C] , and [D] could not be detected by cyclic voltammetry, EPR, or NMR spectroscopy. This finding suggests that dimerization is fast and that there is no dissociation in solution, which was also predicted by DFT calculations. However, EPR measurements of 2 confirmed the presence of small amounts of the radical cation [B] in solution. Single-crystal X-ray diffraction revealed that the products 1 and 2 feature a zigzag E chain in the solid state while 3 and 4 bear a central E cage with a distorted "butterfly-like" geometry. Additionally, 1 can be easily and reversibly converted into a symmetric and an unsymmetric form.

In order to improve and extend the rare class of tetrahedral mixed main group transition metal compounds, a new synthetic route for the complexes [{CpMo(CO)2}2(μ,η2:η2‐PE)] (E=As (1), Sb (2)) is described leading to higher yields and a decrease in reaction steps. Via this route, also the so far unknown heavier analogues containing AsSb (3 a), AsBi (4) and SbBi (5) ligands, respectively, are accessible. Single crystal X‐ray diffraction experiments and DFT calculations reveal that they represent very rare examples of compounds comprising covalent bonds between two different heavy pnictogen atoms, which show multiple bond character and are stabilised without any organic substituents. A simple one‐pot reaction of [CpMo(CO)2]2 with ME(SiMe3)2 (M=Li, K; E=P, As, Sb, Bi) and the subsequent addition of PCl3, AsCl3, SbCl3 or BiCl3, respectively, give the complexes 1–5. This synthesis is also transferable to the already known homo‐dipnictogen complexes [{CpMo(CO)2}2(μ,η2:η2‐E2)] (E=P, As, Sb, Bi) resulting in higher yields comparable to those in the literature reported procedures and allows the introduction of the bulkier and better soluble Cp′ (Cp′=tert butylcyclopentadienyl) ligand.

The modular syntheses of C3-symmetric tris(ferrocenyl)arene-based tris-phosphanes and their homotrinuclear gold(I) complexes are reported. Choosing the arene core allows to fine-tune the exact oxidation potentials and thus to tailor the...

A simple and straightforward synthesis of a new linear trinuclear Cu(I) cluster with polyphosphine ligands is presented. The reaction of this pre-organized Cu3 precursor with En ligand complexes (E = P, As; n = 2, 5) affords discrete complexes exhibiting end-on η(1)-coordination of the E2 ligands or one-dimensional coordination polymers featuring σ-1,3-bridging E5 rings, respectively.