Question

Identify the major product formed in the following reaction sequence:

• A.

  

• B.

  

• C.

  

• D.

  

Hint:

KMnO$_4$ oxidizes all side chains with benzylic hydrogens to COOH groups.

Answer 1

The Correct Option is D

Step (i): Friedel–Crafts acylation — CH$_3$CO group attaches at para position.
Step (ii): Oxidation with KMnO$_4$ — CH$_3$CO group and any methyl groups convert to COOH.
Step (iii): Acidification gives the final dicarboxylic acid — terephthalic acid.