Cerocene
 | |
| Names | |
|---|---|
| IUPAC name
Bis(η8-cyclooctatetraene)cerium | |
| Other names
Cerium di-cyclooctatraene | |
| Identifiers | |
3D model (JSmol) |
|
| |
| |
| Properties | |
| Ce(C8H8)2 | |
| Molar mass | 348.423 |
| Appearance | red crystal |
| Melting point | 290 °C (With Decomposition) |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
| |
Cerocene is a organometallic complex with the chemical formula Ce(C8H8)2 (Ce(cot)2).[1][2] It is a sandwich compound consisting of a central cerium atom and two cyclooctatetraenide rings.
Preparation
[edit]Cerocene can be prepared by reducing cerium(III) di-cyclooctatraene anion salts:[1]
- Ce(C8H8)2K → Ce(C8H8)2 + K+
Chemical properties
[edit]Cerocene decomposes when exposed to water or oxygen to yield non-stoichiometric cerium-oxides and cyclooctratraene derivitives.[2]
It undergoes a disproportionation, leading to an equilibrium between cerocene and a double-decker structure containing two cerium atoms:[2]
- 2 Ce(C8H8)2 ⇌ Ce2(C8H8)3 + C8H8
Although the cyclooctatetraenide ligand is usually considered a dianion and therefore cerocene is identified as a Ce(IV) complex, theoretical and experimental analysis of the compound indicates that is more correctly described containing a Ce(III) atom.[1]
Related compounds
[edit]Cerocene is a known precursor for uranocene, U(C8H8)2:[1]
- Ce(C8H8)2 + UCl3 ⇌ U(C8H8)2 + CeCl3
Cerocene is commonly confused with the compound tris(cyclopentadienyl)cerium.
References
[edit]- 1 2 3 4 Streitwieser, Andrew; Kinsley, Steven A.; Jenson, Chris Henry; Rigsbee, John T. (2004-10-01). "Synthesis and Properties of Di-π-[8]annulenecerium(IV), Cerocene". Organometallics. 23 (22): 5169–5175. ISSN 0276-7333.
- 1 2 3 Walter, Marc D.; Booth, Corwin H.; Lukens, Wayne W.; Andersen, Richard A. (2009). "Cerocene Revisited: The Electronic Structure of and Interconversion Between Ce2(C8H8)3and Ce(C8H8)2". Organometallics. 28 (3): 698–707. doi:10.1021/om7012327. OSTI 948446.