How would you name the following aromatic hydrocarbon?
When it comes to nomenclature of normal alkyl benzenes, we two approaches for naming the compound:
1. alkylbenzene or 2. phenylalkane.
There is a rule that controls the nomenclature procedure:
a) if the the normal alkyl chain is composed of 6 carbon atoms or less, we have to consider the alkyl chain is the substituent on the benzene ring (like this case of n-butylbenzene).
b) if the normal alkyl chain is composed of 7 carbon atoms or more, we have to consider that the benzene ring is the substituent on the alkane chain (with mentioning the position of the phenyl ring indeed)
As an example, here is 2-phenyloctane
And hope this link will help...