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. 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.
12-crown-4, Lithium Ionophore V
3D model (JSmol)
|Density||1.089 g/mL at 25 °C|
|Melting point||16 °C|
|Boiling point||61-70 °C/0.5 mm Hg|
|no hazard statements|
|no precautionary statements|
|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).
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