Cyclic compound
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2008-06-11T12:53:49Z
Thijs!bot
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robot Modifying: [[de:Cyclische Verbindungen]]
In [[organic chemistry]], a '''cyclic compound''' is a [[chemical compound|compound]] in which a series of carbon atoms are connected to form a loop or ring.<ref>{{JerryMarch}}</ref> [[Benzene]] is a well known example. The term "polycyclic" is used when more than one ring is formed in a single molecule for instance in [[naphthalene]], and the term [[macrocycle]] is used for a ring containing more than a dozen atoms.
<gallery>
Image:Benzene bonds.svg|Benzene, a simple cyclic compound.
Image:Naphthalene.png|Naphthalene, a simple polycyclic compound.
Image:Porphyrin.svg|[[Porphyrin]], a simple macrocyclic compound.
</gallery>
Cyclic compounds can be categorized:
* [[Alicyclic compound]]
** [[Cycloalkane]]
** [[Cycloalkene]]
* [[Aromatic hydrocarbon]]
** [[Polycyclic aromatic hydrocarbon]]
* [[Heterocyclic compound]]
* [[Macrocycle]]
Cyclic aldehydes are aldehydes that have their -CHO group bonded directly to the ring. The suffix is -'''carbaldehyde''' or '''carboxaldehyde'''.
== Ring-closing & opening reactions ==
[[Image:Dieckmann Condensation Scheme.png|right|thumb|Dieckman ring-closing reaction]]Related concepts in organic chemistry are so-called '''ring-closing reactions''' in which a cyclic compound is formed and '''ring-opening reactions''' in which rings are opened.
Examples of ring-closing reactions:
* [[Ring-closing metathesis]]
* [[Nazarov cyclization reaction]]
* [[Ruzicka large ring synthesis]]
* [[Dieckmann condensation]]
* [[Wenker synthesis]]
Example of ring-opening reactions:
* A general type of polymerization reaction: [[Ring-opening polymerization]]
* [[Ring opening metathesis polymerisation]]
== External links ==
* {{MeshName|Polycyclic+Compounds}}
* {{MeshName|Macrocyclic+Compounds}}
== References ==
<references/>
[[Category:Organic chemistry]]
[[de:Cyclische Verbindungen]]
[[fr:Composé cyclique]]
[[ja:環式有機化合物]]
[[zh:环状化合物]]