[student1982]

[Borek]

Please read forum rules.

[english]

Benzene is a...special chemical species.

It's just convention.  The ring can be a substituent, or the acyclic portion can be a substituent, depending on what takes priority.

It's the same thing as this:

Why is it styrene instead of 2-phenyl-1-ethene?  It's just a name that's been used for a long time.

[beheada]

And note, even though benzene is the ring and phenol is benzene plus 1 hydroxy group, the functional group of a benzene ring when added is always phenyl. Not sure if there's a reason for that or not. I doubt you'll ever see 1,3,5-cyclohexatriene anywhere...