MolSynapsequestion bank

MolSynapse / Question bank / Hydrocarbons / Aromatic hydrocarbons: benzene reactions and side chain reactions

JEE Advanced levelSingle correct optionDifficulty 3 of 3hc215

The most efficient route from toluene to 3-nitrobenzoic acid is:

A $KMnO X_{4} / OH X^{-}$ , heat; then $H X_{3} O X^{+}$ ; then $HNO X_{3} / H X_{2} SO X_{4}$
B $HNO X_{3} / H X_{2} SO X_{4}$ ; then $KMnO X_{4} / OH X^{-}$ , heat; then $H X_{3} O X^{+}$
C $Br X_{2} / FeBr X_{3}$ ; then $KMnO X_{4} / OH X^{-}$ , heat
D $Cl X_{2}$ , light; then $HNO X_{3} / H X_{2} SO X_{4}$

Answer: A

The carboxyl group is meta directing, so oxidation of the methyl group must precede nitration. Nitrating toluene first gives o/p-nitrotoluene, which would oxidise to 2- or 4-nitrobenzoic acid.

Practice Hydrocarbons More on Aromatic hydrocarbons: benzene reactions and side chain reactions

Previous questionNext question

More questions on Aromatic hydrocarbons: benzene reactions and side chain reactions

Which of the following substituents on a benzene ring are meta directing? JEE Main level
Which of the following, on vigorous oxidation with hot alkaline KMnO4 followed by acidification, give benzoic acid? JEE Main level
Which reagent sequence converts benzene into 1-bromo-3-nitrobenzene most efficiently? JEE Advanced level
To prepare n-butylbenzene from benzene without rearrangement, the best method is: JEE Advanced level
Ethylbenzene is heated with Br2 under light to give X (major). X is heated with alcoholic KOH to give Y. Y is treated with HBr in the presen... JEE Advanced level
Which of the following methods can be used to prepare ethylbenzene from benzene or bromobenzene? JEE Advanced level