Give IUPAC name of the following compound:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 2,4,6-Trinitrobenzoic acid
When a benzene ring carries a –COOH group, the compound is named as a derivative of benzoic acid. The rules are:
–COOH is the principal group, so it gives the suffix “benzoic acid” and is never named as a prefix.
The ring carbon carrying –COOH is C-1.
The ring is numbered from C-1 in the direction that gives the other substituents the lowest locants.
\( \ce{-NO2} \) is always named as the prefix “nitro”.
In the given compound, the two –\( \ce{NO2} \) groups next to the –COOH carbon are at C-2 and C-6, and the third is opposite it, at C-4. So the name is 2,4,6-trinitrobenzoic acid.