Chemistry · Alcohols, Phenols and Ether
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Phenol is more reactive than benzene towards electrophilic substitution. This characteristic is due to which of the following?
- A
Hydrogen bonding
- B
Inductive effect
- C
Strong mesomeric effect
- D
Weak mesomeric effect
The presence of the hydroxyl group in phenol allows for extensive resonance delocalization of electrons in the benzene ring, resulting in a strong mesomeric effect. This mesomeric effect stabilizes the positive charge on the intermediate during electrophilic substitution, making phenol more reactive. Hence, option C is correct.
Although phenol can form hydrogen bonds with other molecules or functional groups, it does not directly contribute to its increased reactivity towards electrophilic substitution.
The inductive effect refers to the electron-donating or electron-withdrawing effect of adjacent atoms or functional groups. While the hydroxyl group in phenol does have a slightly electron-withdrawing effect, it is the mesomeric effect that primarily influences its reactivity.
This is the correct option.The presence of the hydroxyl group in phenol allows for extensive resonance delocalization of electrons in the benzene ring, resulting in a strong mesomeric effect. This mesomeric effect stabilizes the positive charge on the intermediate during electrophilic substitution, making phenol more reactive.
Phenol exhibits a strong mesomeric effect due to the presence of the hydroxyl group, and not a weak mesomeric effect.
Tagged under Chemistry · Alcohols, Phenols and Ether · 2022