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cyclooctatetraene

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cyclooctatetraene

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Also known as 1,3,5,7-cyclooctatetraene, cycloocta-1,3,5,7-tetraene, COT, [8]-annulene, (Z,Z,Z,Z)-1,3,5,7-cyclooctatetraene

1,3,5,7-Cyclooctatetraene (COT) is an unsaturated derivative of cyclooctane. It is a colorless flammable liquid at room temperature. COT is an antiaromatic compound as it possesses 8 π electrons. In contrast to the aromaticity commonly seen in benzene rings; antiaromaticity destabilises the COT molecule. This destabilisation effect is so strong that COT avoids it by adopting a non-planar 'tub' conformation, which prevents all of the π orbitals from forming a single conjugated system. As a result, COT possesses significant polyene character and will undergo many reactions that benzene rings wil

Chemical data

Formula
C8H8
Molecular weight
104.15 g/mol
IUPAC name
cyclooctatetraene
SMILES
C\1=C\C=C/C=C\C=C1
InChIKey
KDUIUFJBNGTBMD-DLMDZQPMSA-N
XLogP
3.1
Polar surface area
0 Ų
H-bond donors
0
H-bond acceptors
0
Formal charge
0

via PubChem

Wikidata facts

Subclass of
annulene
Has part
hydrogen
Mass
104.062600256
Show 5 more facts
canonical SMILES
C1=CC=CC=CC=C1
chemical formula
C₈H₈
Commons category
Cyclooctatetraene
isomeric SMILES
C1=C/C=C\C=C/C=C\1
melting point
-5
Sources (2)

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Encyclopedic overview

9 sections
Contents
  • History
  • Structure and bonding
  • Synthesis
  • Derivatives
  • Natural occurrence
  • Reactions
  • Cyclooctatetraenide as a ligand and ligand precursor
  • See also
  • References

1,3,5,7-Cyclooctatetraene (COT) is an unsaturated derivative of cyclooctane. It is a colorless flammable liquid at room temperature. COT is an antiaromatic compound as it possesses 8 π electrons. In contrast to the aromaticity commonly seen in benzene rings; antiaromaticity destabilises the COT molecule. This destabilisation effect is so strong that COT avoids it by adopting a non-planar 'tub' conformation, which prevents all of the π orbitals from forming a single conjugated system. As a result, COT possesses significant polyene character and will undergo many reactions that benzene rings will not. This been the subject of much research and historically some controversy.

==History== 1,3,5,7-Cyclooctatetraene was initially synthesized by Richard Willstätter in Munich in 1905 using pseudopelletierine as the starting material and the Hofmann elimination as the key transformation: class=skin-invert-image|450px|Willstätter's synthesis of cyclooctatetraene (1905).

Excerpted from Wikipedia’s “cyclooctatetraene” article, available under the CC BY-SA 4.0 licence.

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