Give reasons for the following:
Benzoic acid does not undergo Friedel-Crafts reaction.
Benzoic acid does not undergo Friedel-Crafts reaction.
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Solution and Explanation
The –COOH group is strongly electron withdrawing due to its –M (–mesomeric) and –I (–inductive) effects.
This deactivates the benzene ring towards electrophilic substitution reactions like Friedel-Crafts alkylation or acylation.
Also, the –COOH group can coordinate with the Lewis acid catalyst (like AlCl$_3$), forming a complex that reduces the availability of the catalyst for generating the electrophile.
Therefore, benzoic acid does not undergo Friedel-Crafts reaction.
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