Aryl group

In organic chemistry, an aryl is any functional group or substituent derived from an aromatic ring, usually an aromatic hydrocarbon, such as phenyl and naphthyl.^[1] "Aryl" is used for the sake of abbreviation or generalization, and "Ar" is used as a placeholder for the aryl group in chemical structure diagrams, analogous to “R” used for any organic substituent. “Ar” is not to be confused with the elemental symbol for argon.

A simple aryl group is phenyl (C₆H₅−), a group derived from benzene. Examples of other aryl groups consist of:

• The tolyl group (CH₃C₆H₄−) which is derived from toluene (methylbenzene)
• The xylyl group ((CH₃)₂C₆H₃−), which is derived from xylene (dimethylbenzene)
• The naphthyl group (C₁₀H₇−), which is derived from naphthalene

Arylation is the process in which an aryl group is attached to a substituent. It is typically achieved by cross-coupling reactions.