Organic Functional Groups

FG6.  Aromatics

An aromatic is a particularly stable structure that is frequently seen in organic chemistry.  Aromatics are planar, cyclic, fully conjugated systems with odd numbers of electron pairs in their conjugated π system.   Benzene is the most common example of an aromatic molecule.  It is a six-membered ring with alternating single and double bonds.  It has three π bonds, and so it has three electron pairs in its π system.

There are a number of common derivatives of benzene with names that you should remember.

There is also a peculiar way of naming benzene derivatives that have two substituents on the benzene ring.  The prefixes o-, m- and p- denote 1,2-disubstitution, 1,3-disubstitution and 1,4-disubstitution, respectively.


Problem FG61. 

Draw the following compounds.

a)  p-nitrotoluene        b)  o-chloroaniline        c)  m-methylphenol

d)  m-chlorobenzyl alcohol        e)  o-bromobenzaldehyde    f)  p-fluorobenzoic acid

g)  2,4-dimethylphenol        h)  2,5-dichlorotoluene        i)  2,4,5-trimethylaniline



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