Cyclooctatetraenide anion

Cyclooctatetraenide anion
Names
Preferred IUPAC name
Cyclooctatetraenediide
Identifiers
3D model (JSmol)
  • c1=c[cH-]c=c[cH-]c=c1
Properties
C8H82−
Molar mass 104.15 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

In chemistry, the cyclooctatetraenide anion or cyclooctatetraenide, more precisely cyclooctatetraenediide, is an aromatic species with a formula of [C8H8]2− and abbreviated as COT2−. It is the dianion of cyclooctatetraene. Salts of the cyclooctatetraenide anion can be stable, e.g., Dipotassium cyclooctatetraenide or disodium cyclooctatetraenide. More complex coordination compounds are known as cyclooctatetraenide complexes, such as the actinocenes.

The structure is a planar symmetric octagon stabilized by resonance, meaning each atom bears a charge of −1/4. The length of the bond between carbon atoms is 1.432 Å. There are 10 π electrons.[1] The structure can serve as a ligand with various metals.

  1. ^ Jug, Karl (November 1984). "Aromaticity in unusual heteropolar monocyclic rings with (4n + 2) π electrons". The Journal of Organic Chemistry. 49 (23): 4475–4478. doi:10.1021/jo00197a029.