Imidazolium-based ionic liquids served to selectively methylate terminal chalcogenide ligands of chalcogenidometalate clusters [Sn10S16O4(SMe)4]4−, [Mn4Sn4Se13(SeMe)4]6−, and [Hg6Te10(TeMe)2]6−.

Compounds consisting of [M(1,2-disila-[3n]crown-n)] (M = Mg, Ca, Sr, Ba; n = 5, 6) and [Ba(1,2-disila-benzo[18]crown-6)] cations and different anions were obtained by equimolar reaction of the hybrid disila-crown ethers 1,2-disila[15]crown-5 (1), 1,2-disila[18]crown-6 (2) and 1,2-disila-benzo[18]crown-6 (7) with alkaline earth metal salts. Even with strongly coordinating anions such as Br or I stable complexes could be obtained, showing the good coordination ability of these ligands. The structures of all coordination compounds were determined via single crystal X-ray diffraction (XRD). By means of DFT calculations, the complexation ability of 1,2-disila[15]crown-5 (1) towards magnesium bromide was determined to be considerably higher compared to [15]crown-5. The opposite case was observed in solution as the exchange of calcium cations between [18]crown-6 and 1,2-disila[18]crown-6 (2) was studied via dynamic proton nuclear magnetic resonance (NMR) spectroscopy.

The use of ionic liquids (C C Im)[BF ] with long alkyl chains (n=10, 12) in the ionothermal treatment of Na [HgTe ] led to lamellar crystal structures with molecular macrocyclic anions [Hg Te ] (1), the heaviest known topological relative of porphyrin. [Hg Te ] differs from porphyrin by the absence of an electronic π-system, which prevents a "global" aromaticity. Quantum chemical studies reveal instead small ring currents in the pyrrole-type five-membered rings that indicate weak local (σ) aromaticity. As a result of their lamellar nature, the compounds are promising candidates for the formation of sheets containing chalcogenidometalate anions.

Mismatched complexes of the alkali metals cations Li + and Na + were synthesized from 1,2-disila[18]crown-6 (1 and 2) and of K + from 1,2,4,5-tetrasila[18]crown-6 (4). In these alkali metal complexes, not all crown ether O atoms participate in the coordination, which depicts the coordination ability of the C-, Si/C-, and Si-bonded O atoms. Furthermore, the inverse case-the coordination of the large Ba 2+ ion by the relatively small ligand 1,2-disila[15]crown-5-was investigated, yielding the dinuclear complex 5. This structure represents a first outlook on sandwich complexes based on hybrid crown ethers.

The ternary telluridomercurate Na2[HgTe2] (1) was formed by fusion of Na2Te and HgTe at 600 °C and further treated in the ionic liquid (C4C1Im)[BF4] (C4C1Im = 1‐butyl‐3‐methylimidazolium) at moderately elevated temperatures (60 °C), leading to replacement of the Na+ cations with (C4C1Im)+ and re‐arrangement of the inorganic substructure. As a result, we obtained the telluridomercurate (C4C1Im)2[HgTe2] (2) and the tellurido/ditelluridomercurate (C4C1Im)2[Hg2Te4] (3) besides polytellurides and HgTe as by‐products. The heavy atom compositions of the compounds were confirmed by micro X‐ray fluorescence spectroscopy (μ‐XFS), and their structures were determined by single‐crystal diffraction. The cation‐exchanged salts were further investigated by UV/Vis spectroscopy, indicating narrow band‐gap optical transitions at 2.80 eV (2) and 1.63 eV (3), in agreement with their visible yellow or reddish‐black color, respectively.