Home > Community > Reactivity comparison of phenol and toluene towards electrophilic substitution
Upvote

21

Downvote
+ Phenols
+ Chemistry
Posted by
Melanie Jiang

Reactivity comparison of phenol and toluene towards electrophilic substitution

Captain's Italian Food  Follow

You have to make a comparison between phenol and toluene. You have identified what toluene does, but you haven't described what phenol does.

The hydroxyl group in phenol increases electron density in the ring by resonance (+M effect). Note that the methyl group in toluene increases electron density only by hyperconjugation and inductive effect.

Resonance effects are generally far more superior to hyperconjugation. Hence, without doubt, phenol is more activated towards EAS as compared to toluene.

More

Upvote

VOTE

Downvote
Jim Homan  Follow
@Rahul Resonance involves direct conjugation of an electron pair on an atom into the conjugated system. However, for hyperconjugation, you have to first break the C-H bond, and only then the lone pair on the carbon atom formed can resonate (Hyperconjugation is called "no bond resonance" if you recall) Hence, resonance activation of ring is better.More
Upvote

VOTE

Downvote
Etienne Jooken  Follow
"Resonance effects are generally far more superior to hyperconjugation" - Why?More
Upvote

VOTE

Downvote