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Names | |||
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Preferred IUPAC name 1,4,7,10-Tetraoxacyclododecane | |||
Other names 12-crown-4, Lithium Ionophore V | |||
Identifiers | |||
3D model (JSmol) | |||
1363064 | |||
ChEBI | |||
ChemSpider | |||
ECHA InfoCard | 100.005.488 | ||
EC Number |
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3287 | |||
PubChem CID | |||
UNII | |||
CompTox Dashboard (EPA) | |||
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Properties | |||
C8H16O4 | |||
Molar mass | 176.21 | ||
Density | 1.089 g/mL at 25 °C | ||
Melting point | 16 °C | ||
Boiling point | 61-70 °C/0.5 mm Hg | ||
Miscible | |||
Hazards | |||
Flash point | 113 °C (235 °F; 386 K) | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
12-Crown-4, also called 1,4,7,10-tetraoxacyclododecane and lithium ionophore V, is a crown ether with the formula C8H16O4. It is a cyclic tetramer of ethylene oxide which is specific for the lithium cation.
12-Crown-4 can be synthesized using a modified Williamson ether synthesis, using LiClO4 as a templating cation: [1]
It also forms from the cyclic oligomerization of ethylene oxide in the presence of gaseous boron trifluoride. [2]
Like other crown ethers, 12-crown-4 complexes with alkali metal cations. The cavity diameter of 1.2-1.5 Å gives it a high selectivity towards the lithium cation (ionic diameter 1.36 Å) [2]
Its point group is S4. The dipole moment of 12-crown-4 varies with solvent and temperature. At 25 °C, the dipole moment of 12-crown-4 was determined as 2.33 ± 0.03 D in cyclohexane and 2.46 ± 0.01 D in benzene. [3]