In the following questions a statement of Assertion (A) followed by a...
Toluene has −CH3 group attached to benzene ring. CH3 group is electron withdrawing group which deactivates benzene ring due to hyperconjugation effect and increases electron density on ortho and para positions for the attack of electrophiles.
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In the following questions a statement of Assertion (A) followed by a...
Explanation:
Assertion (A):
Toluene on Friedel-Crafts methylation gives o- and p-xylene.
Reason (R):
CH3-group bonded to the benzene ring increases electron density at o- and p- position.
Explanation:
Assertion (A) and Reason (R)
Both Assertion (A) and Reason (R) are correct, and Reason (R) is the correct explanation of Assertion (A).
Explanation:
- Toluene undergoes Friedel-Crafts methylation in the presence of a Lewis acid catalyst like AlCl3 to form o- and p-xylene as the major products.
- The presence of the CH3 group in toluene increases the electron density on the benzene ring, making the o- and p- positions more susceptible to electrophilic attack during the Friedel-Crafts reaction.
- This increase in electron density at the o- and p- positions results in the preferential substitution at these positions, leading to the formation of o- and p-xylene.
Therefore, the Reason (R) correctly explains why toluene on Friedel-Crafts methylation gives o- and p-xylene, supporting Assertion (A). Hence, Option (a) is the correct choice.