C6H5

Nomenclature

Usually, a "phenyl group" is synonymous with C₆H₅− and is represented by the symbol Ph (archaically, Φ), or Ø. Benzene is sometimes denoted as PhH. Phenyl groups are generally attached to other atoms or groups. For example, triphenylmethane (Ph₃CH) has three phenyl groups attached to the same carbon center. Many or even most phenyl compounds are not described with the term "phenyl". For example, the chloro derivative C₆H₅Cl is normally called chlorobenzene, although it could be called phenyl chloride. In special (and rare) cases, isolated phenyl groups are detected: the phenyl anion (C₆H−5), the phenyl cation (C₆H+5), and the phenyl radical (C
₆H
₅).