Unusual centrosymmetric structure of [M(18-crown-6)](+) (M = Rb, Cs and NH4) complexes stabilized in an environment of hexachloridoantimonate(V) anions

On the molecular architectures of siloxane coordination compounds: (re-)investigating the coordination of the cyclodimethylsiloxanes Dn(n= 5–8) towards alkali metal ions

Cyclodimethylsiloxanes have been used as complex ligands and silyl-ether bonding towards various cations is explored stepwise. Compounds with unprecedented coordination modes as well as novel molecular architectures are obtained and characterized.

Hybrid Disila-Crown Ethers as Hosts for Ammonium Cations: The O–Si–Si–O Linkage as an Acceptor for Hydrogen Bonding

Host-guest chemistry was performed with disilane-bearing crown ethers and the ammonium cation. Equimolar reactions of 1,2-disila[18]crown-6 (1) or 1,2-disila-benzo[18]crown-6 (2) and NH4PF6 in dichloromethane yielded the respective compounds [NH4(1,2-disila[18]crown-6)]PF6 (3) and [NH4(1,2-disila-benzo[18]crown-6)]PF6 (4). According to X-ray crystallographic, NMR, and IR experiments, the uncommon hydrogen bonding motif O(Si)∙∙∙H could be observed and the use of cooperative effects of ethylene and disilane bridges as an effective way to incorporate guest molecules was illustrated.