Re: Why are aromatic compounds aromatic?

While many compounds fit the chemical definition of aromatic, in general 
there is no strong correlation between chemical aromaticy and the smell of 
the compound.  Although most of the simple aromatic chemicals such as benzene 
do have strong and/or pleasant smells, this is a characteristic of 
volatile organic compounds as a whole.  Higher molecular weight aromatic 
compounds often do not have strong smells.  

There are many other classes of compounds that have strong smells when 
they are volatile.  Esters, for example, are the primary constituents of 
many perfumes and flavor enhancers.  Thiols and amines very often also 
have extremely strong (and often unpleasant) smells.

The term “aromatic” is therefore a bit misleading.  The term became 
associated with this class of compounds historically because the first 
aromatic compounds studied tended to be the simple low molecular weight, 
and therefore volatile, examples of these compounds.

I hope this helps.