Cyclic compound 3949010 218617209 2008-06-11T12:53:49Z Thijs!bot 1392310 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]]