Cyanocarbon
Cyanocarbons are a group of chemical compounds that contain several cyanide functional groups. Such substances generally are classified as organic compounds, since they are formally derived from hydrocarbons by replacing one or more hydrogen atoms with a cyanide group.[1] The parent member is C(CN)4 (tetracyanomethane, also known as carbon tetracyanide). Organic chemists often refer to cyanides as nitriles.
In general, cyanide is an electronegative substituent. Thus, for example, cyanide-substituted carboxylic acids tend to be stronger than the parents. The cyanide group can also stabilize anions by delocalizing negative charge as revealed by resonance structures.
Definition and examples
Cyanocarbons are organic compounds bearing enough cyano functional groups to significantly alter their chemical properties.[1]
Important cyanocarbons:
- Tetracyanoethylene, which readily reduces to a stable anion, unlike most ethene derivatives
- Pentacyanocyclopentadiene, which forms a stable anion by ionization of the C-H bond.
- Tetracyanoethylene oxide, an electrophilic epoxide that undergoes ready scission of its C-C bond.
- Tetracyanoquinodimethane, C6H4-1,4-(C(CN)2)2, a powerful electron acceptor.
- Cyanoform (tricyanomethane), (NC)3CH
References
- Webster, Owen W. "Cyanocarbons: a classic example of discovery-driven research" Journal of Polymer Science, Part A: Polymer Chemistry 2001, volume, 40, pp. 210-221. doi:10.1002/pola.10087