Cyclic compound

In chemistry, a cyclic compound is a compound in which a series of atoms is connected to form a loop or ring.^[1] While the vast majority of cyclic compounds are organic, a few inorganic substances form cyclic compounds as well, including sulfur, silanes, phosphanes, phosphoric acid, and triboric acid. Cyclic compounds may or may not be aromatic. 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.

Alicyclic compound are named according to the IUPAC system of nomenclature by attaching the prefix cyclo- to the name of the corresponding open chain hydrocarbon possessing the same number of carbon atoms. The common names resemble the IUPAC names. For example: Cyclo pantane, cyclo butane etc....

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

• open-chain compound
• Ring expansion and ring contraction
• Macrocycle
• Effective molarity

External links

• MeSH Polycyclic+Compounds
• MeSH Macrocyclic+Compounds

References

1. ^ March, Jerry (1985), Advanced Organic Chemistry: Reactions, Mechanisms, and Structure (3rd ed.), New York: Wiley, ISBN 0-471-85472-7