Aryl

An aryl group (abbreviated Ar) is an organic chemical group having an aromatic backbone. Aryl is thus the common name for a monovalent group of atoms derived from aromatic hydrocarbons by removal of a bound to the ring hydrogen atom. Most aryl radicals derived from benzene ( C6H6), the simplest aryl group is phenyl (Ph ), ( - C6H5). Aryl radicals can occur either as a fragment of a molecule ( see table) or as an unstable free radical. Aryl cations are formed as reactive intermediates in the elimination of nitrogen from aryl diazonium salts, the so-called " boiling " of aryl diazonium salts to form aromatic alcohols (eg, phenols). Aryl anions occur as well as reactive intermediates in organic synthesis and are more stable than aryl cations.

The term aryl is especially used when formulated in general terms and does not want to specify more precisely to which aromatic group it is.

Aryl groups, in contrast to the term alkyl is used to refer to a group which is not aromatic. There are also combinations of alkyl radicals and aryl radicals, an example is the benzyl radical [- CH2 - C6H5 ], of the toluene derived by removal of a hydrogen atom of the methyl group.

As biaryls (not: diaryls ) refers to compounds in which two aryl groups are linked together via a single bond. The simplest biaryl is biphenyl.

The chemical properties see heading aromatics.