Monoaryl

Monoaryl compounds are organic molecules that contain exactly one aryl substituent. An aryl group is derived from an aromatic ring by removing one hydrogen, with the phenyl group being the most common example. Substituted aryl groups are also included under the term monoaryl.

Common examples of monoaryl compounds include toluene (methylbenzene), chlorobenzene, anisole (methoxybenzene), benzaldehyde, and phenylacetic acid. Each of these features a single aryl ring attached to another functional group or substituent, and they differ in the nature of that attachment.

In contrast, diaryl and polyaryl compounds contain two or more aryl groups. For instance, biphenyl consists of two phenyl rings connected by a single bond, while diphenyl ether contains two phenyl rings linked through an oxygen atom. The distinction between monoaryl and higher-aryl compounds is important in reactivity, synthesis planning, and applications.

Applications and relevance: monoaryl compounds serve as important building blocks in organic synthesis, pharmaceuticals, dyes, and polymers. They are common solvents (e.g., toluene) or starting materials for further functionalization, such as forming carbon–carbon or carbon–heteroatom bonds. The properties of monoaryl compounds—such as boiling point, density, and reactivity—are influenced by the substituents on the aryl ring, enabling a wide range of uses in research and industry.