metaphenyl

Metaphenyl is a term encountered in organic chemistry to denote a phenyl substituent located at the meta position relative to another reference substituent on a benzene ring. It is not a distinct chemical species by itself and does not define a unique molecular formula; rather, metaphenyl describes a substitution pattern on an aromatic system. In modern nomenclature, the descriptor m- or meta- is preferred for specifying a meta relationship, and metaphenyl as a standalone label has largely fallen out of routine use outside historical or niche contexts.

In practice, metaphenyl appears in the naming of substituted arenes where the exact substitution pattern matters for properties or reactivity. The meta relationship indicates that the substituent of interest is three atoms away around the ring from the reference point (as opposed to ortho or para positions). This concept is part of the broader system of descriptive designations used for benzene derivatives.

Because contemporary chemical literature typically uses explicit locants (for example 3-phenyl, m-phenyl, or meta-phenyl) rather than the older metaphenyl label, the term metaphenyl can seem archaic. When encountered, it is most often found in historical syntheses, older patent literature, or writings that preserve historical naming conventions. In current practice, precision is achieved with locants or with the conventional meta- prefix attached to the substituent name.