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Bis(benzo-15-crown-5-κO)strontium bis-(triiodide).
Christine Walbaum1, Ingo Pantenburg, Gerd Meyer
1Institut für Anorganische Chemie, Universität zu Köln, Greinstrasse 6, D-50939 Köln, Germany.
Acta Crystallographica. Section E, Structure Reports Online
|January 5, 2011
Summary
Researchers synthesized a novel strontium compound, [Sr(benzo-15-crown-5)2](I3)2, featuring layered structures of strontium-crown ether cations and triiodide anions. This crystal structure offers insights into coordination chemistry and supramolecular assembly.
Area of Science:
- Inorganic Chemistry
- Crystallography
- Supramolecular Chemistry
Background:
- Strontium chloride (SrCl2) and benzo-15-crown-5 are known for their coordination properties.
- Iodine (I2) can form polyiodide anions, such as triiodide (I3-).
- Crown ethers are macrocyclic compounds that can complex metal cations.
Purpose of the Study:
- To synthesize and characterize a novel strontium-crown ether complex containing triiodide anions.
- To elucidate the crystal structure and supramolecular arrangement of the title compound.
- To investigate the coordination behavior of strontium with benzo-15-crown-5 in the presence of triiodide.
Main Methods:
- Single crystal X-ray diffraction was used to determine the crystal structure.
- Slow evaporation technique was employed for crystal growth from an ethanol/dichloromethane solution.
- Synthesis involved reacting strontium chloride, benzo-15-crown-5, and iodine.
Main Results:
- The title compound, [Sr(C14H20O5)2](I3)2, was successfully synthesized and characterized.
- The crystal structure reveals sandwich-like [Sr(benzo-15-crown-5)2](2+) cations and isolated linear I3- anions.
- These ions are arranged in alternating layers parallel to the (010) crystallographic plane.
Conclusions:
- The study successfully synthesized a novel strontium complex with benzo-15-crown-5 and triiodide.
- The crystal structure demonstrates a layered arrangement of cations and anions, highlighting supramolecular assembly.
- The findings contribute to the understanding of strontium coordination chemistry and the formation of polyiodide complexes.
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