|Jmol-3D images||Image 1|
|Molar mass||220.26 g mol−1|
|Appearance||Clear, colorless liquid|
|Density||1.113 g cm-3 (at 20 °C)|
|Boiling point||116 °C (241 °F; 389 K) at 240 Pa|
|Refractive index (nD)||1.465|
|Std enthalpy of
|-881.1--877.1 kJ mol-1|
|Std enthalpy of
|-5.9157--5.9129 MJ mol-1|
|GHS signal word||WARNING|
|GHS hazard statements||H302, H315, H319|
|GHS precautionary statements||P305+351+338|
|Flash point||113 °C (235 °F; 386 K)|
|Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)|
|(what is: / ?)|
15-Crown-5 is a crown ether with the formula C10H20O5. It is a cyclic pentamer of ethylene oxide that has been shown to complex with various cations, including sodium (Na+) and potassium (K+), however, it is complementary to Na+ and thus has a higher selectivity for Na+ ions.
Analogous to 18-crown-6, 15-crown-5 can bind to sodium ions, making the ionic compounds soluble in hydrophobic phases.
However, 15-crown-5 allows the first-row transition metal cations to fit snugly inside the cavity of 15-crown-5, which is too small to be included in 18-crown-6. The binding of transition metal cations results in multiple hydrogen-bonded interactions from both equatorial and axial aqua ligands, such that highly crystalline solid-state supramolecular polymers were isolated. Metal salts isolated in this form includes Co(ClO4)2, Ni(ClO4)2, Cu(ClO4)2 and Zn(ClO4)2. Seven coordinate species are most common for transition metal ions complexes of 15-crown-5, with the crown ether occupying the equatorial plane, along with 2 axial aqua ligands.
15-crown-5 have also been used to isolate some specific, intriguing oxonium ions. For example, from a solution of tetrachloroauric acid, the oxonium ion [H7O3]+ have been isolated as the salt [(H7O3)(15-crown-5)2][AuCl4]. Neutron diffraction studies revealed a sandwich structure, which shows a chain of water with remarkably long O-H bond (1.12 Å) in the acidic proton, but with a very short OH•••O distance (1.32 Å).
A derivative of 15-crown-5, benzo-15-crown-5, have been used to produce carbide complexes. The first step of this method is to synthesize an acetylide complex from the corresponding metal carbonyl, followed by abstracting the acidic proton in the acetylide with a strong base. Benzo-15-crown-6 is then applied to sequester the K+ counter ions to give the free carbide complex.
- "15-crown-5 - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 16 September 2004. Identification and Related Records. Retrieved 11 October 2011.
- Takeda, Y., et al. (1988). "A Conductance Study of 1:1 Complexes of 15-Crown-5, 16-Crown-5, and Benzo-15-crown-5 with Alkali Metal Ions in Nonaqueous Solvents". Bulletin of the Chemical Society of Japan 61 (3): 627–632.
- Chen, Chun-Yen, et al. (2006). "Potassium ion recognition by 15-crown-5 functionalized CdSe/ZnS quantum dots in H2O". Chem. Comm. (3): 263–265. doi:10.1039/B512677K.
- Jonathan W. Steed; Jerry L. Atwood (2009). Supramolecular Chemistry, 2nd edition. Wiley. ISBN 978-0-470-51233-3.
- "Mesogenic Properties of 15-Crown-5-Ether - Derivatives". Retrieved 2008-11-19.[dead link]
- Klok, H.A., et al. (1997). "Novel benzo-15-crown-5 functionalized α-olefin/CO terpolymers for membrane applications". Macromolecular Chemistry and Physics 198 (9): 2759–2768. doi:10.1002/macp.1997.021980908.
- Fedorova, O.A., et al. (2005). "Facile synthesis of novel styryl ligands containing a 15-crown-5 ether moiety". Arkivoc xv: 12–24.