A cubic Fe4Mo4 oxo framework and its reversible four-electron redox chemistry.

The potential of iron molybdates as catalysts in the Formox process stimulates research on aggregated but molecular iron-molybdenum oxo compounds. In this context, [(Me3TACN)Fe](OTf)2 was reacted with (nBu4N)2[MoO4], which led to an oxo cluster, [[(Me3TACN)Fe][μ-(MoO4-κ(3)O,O',O″)]]4 (1, Fe4Mo4) with a distorted cubic structure, where the corners are occupied by (Me3TACN)Fe(2+) and [Mo═O](4+) units in an alternating fashion, being bridged by oxido ligands. The cyclic voltammogram revealed four reversible oxidation waves that are assigned to four consecutive Fe(II) → Fe(III) transfers and motivated attempts to isolate compounds containing the respective cations.

Mass Spectrometry and Gas-Phase Chemistry of Bismuth-Oxido Clusters.

The mass spectrometric characterisation of bismuth-oxido clusters is described together with tandem mass spectrometric experiments aimed at investigating their gas-phase chemistry. Clusters with different ligand shells (nitrate, salicylates, and methacrylate) and different sizes ({Bi O }, {Bi O }, and {Bi O }) were selected for this study. The following aspects were addressed by (tandem) electrospray ionisation Fourier-transform ion-cyclotron-resonance (ESI-FTICR) mass spectrometry: 1) Electrospray ionisation was used successfully for the generation of intact cluster ions, but led to rather complicated distributions of charge states and solvent adducts.

Generation of a dynamic system of three-dimensional tetrahedral polycatenanes.

: A dynamic combinatorial library of polycatenated tetrahedra was prepared by complexation between a dynamic FeL tetrahedral cage, constructed from ligands containing an electron‐deficient naphthalenediimide core, and an electron‐rich aromatic crown ether, 1,5‐dinaphtho[38]crown‐10. The highest order species in the library is the tetrahedral [7]catenane.[Image: see text]

Deposition of ordered layers of tetralactam macrocycles and ether rotaxanes on pyridine-terminated self-assembled monolayers on gold.

The deposition of tetralactam macrocycles and the corresponding benzyl ether rotaxanes on gold substrates is investigated for the first time exploiting metallo-supramolecular chemistry. Two pyridine-terminated self-assembled monolayers (SAMs) are developed that are used as well-ordered template layers. The two SAMs differ with respect to the rigidity of the terminal pyridines as shown by angle-resolved near-edge X-ray absorption fine structure (NEXAFS) spectroscopy.

[4]Pseudorotaxanes with remarkable self-sorting selectivities.

The synthesis and characterization of several self-assembled [4]pseudorotaxanes is reported, some of which form in a programmed way based on two similar yet orthogonal crown ether/secondary ammonium ion binding motifs. A preference for the formation of a [4]pseudorotaxane with an antiparallel rather than parallel alignment of crown ether building blocks is observed even in the absence of such orthogonal binding sites, when a homodivalent axle is used.