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18-crown-6
Sign in to saveAlso known as 18-crown-6 ether, ethylene oxide cyclic hexamer, 1,4,7,10,13,16-hexaoxacyclooctadecane
18-Crown-6 is an organic compound with the formula [C2H4O]6 and the IUPAC name of 1,4,7,10,13,16-hexaoxacyclooctadecane. It is a white, hygroscopic crystalline solid with a low melting point. Like other crown ethers, 18-crown-6 functions as a ligand for some metal cations with a particular affinity for potassium cations (binding constant in methanol: 106 M−1). The point group of 18-crown-6 is S6. The dipole moment of 18-crown-6 is solvent- and temperature-dependent. Below 25 °C, the dipole moment of 18-crown-6 is in cyclohexane and in benzene. The synthesis of the crown ethers led to
Chemical data
- Formula
- C12H24O6
- Molecular weight
- 264.31 g/mol
- IUPAC name
- 1,4,7,10,13,16-hexaoxacyclooctadecane
- SMILES
- C1COCCOCCOCCOCCOCCO1
- InChIKey
- XEZNGIUYQVAUSS-UHFFFAOYSA-N
- XLogP
- -0.7
- Polar surface area
- 55.4 Ų
- H-bond donors
- 0
- H-bond acceptors
- 6
- Formal charge
- 0
via PubChem
Wikidata facts
- Subclass of
- crown ether
- Has part
- hydrogen
- Mass
- 264.157
Show 4 more facts
- Commons category
- 18-crown-6
- chemical formula
- C₁₂H₂₄O₆
- canonical SMILES
- C1COCCOCCOCCOCCOCCO1
- melting point
- 39.0
via Wikidata · CC0
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Encyclopedic overview
5 sectionsContents
- Synthesis
- Reactions
- Applications
- References
- External links
18-Crown-6 is an organic compound with the formula [C2H4O]6 and the IUPAC name of 1,4,7,10,13,16-hexaoxacyclooctadecane. It is a white, hygroscopic crystalline solid with a low melting point. Like other crown ethers, 18-crown-6 functions as a ligand for some metal cations with a particular affinity for potassium cations (binding constant in methanol: 106 M−1). The point group of 18-crown-6 is S6. The dipole moment of 18-crown-6 is solvent- and temperature-dependent. Below 25 °C, the dipole moment of 18-crown-6 is in cyclohexane and in benzene. The synthesis of the crown ethers led to the awarding of the Nobel Prize in Chemistry to Charles J. Pedersen.
==Synthesis== This compound is prepared by a modified Williamson ether synthesis in the presence of a templating cation: (CH2OCH2CH2Cl)2 + (CH2OCH2CH2OH)2 + 2 KOH → (CH2CH2O)6 + 2 KCl + 2 H2O
Excerpted from Wikipedia’s “18-crown-6” article, available under the CC BY-SA 4.0 licence.