Cyclic compound
In chemistry, a cyclic compound is a, mostly organic, compound in which a series of atoms are connected to form a loop or ring.[1] 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.
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Benzene, a simple cyclic compound. -
Naphthalene, a simple polycyclic compound. -
Porphyrin, a simple macrocyclic compound. -
Pentazole, an inorganic cyclic compound.
Categorization
Cyclic compounds can be categorized:
Ring-closing & opening reactions
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
- Radical cyclization
Example of ring-opening reactions:
- A general type of polymerization reaction: Ring-opening polymerization
- Ring opening metathesis polymerisation
See also
External links
- Polycyclic+Compounds at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
- Macrocyclic+Compounds at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
References
- ^ March, Jerry (1985), Advanced Organic Chemistry: Reactions, Mechanisms, and Structure, 3rd edition, New York: Wiley, ISBN 9780471854722, OCLC 642506595