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Why during nitration of N-phenylbenzamide the $\ce{NO2}$ group is directed at para-position of the ring attached to the nitrogen atom? Okay, I understand that this is due to the para directing effect of the $\ce{>NH}$ group. But carbonyl $\ce{>C=O}$ group has a meta directing effect, then why is $\ce{NO2}$ not directed to the meta-position of the benzene ring attached to carbonyl group?

In the following reaction

N-phenylbenzamide

(1) $\ce{NO2}$ group at meta position w.r.t. Ring 2
(2) $\ce{NO2}$ group at para position w.r.t. Ring 1
(3) $\ce{NO2}$ group at para position w.r.t. Ring 2
(4) $\ce{NO2}$ group at meta position w.r.t. Ring 1

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  • $\begingroup$ The carbonyl attached to ring 2 is meta directing but deactivating. $\endgroup$ – Waylander Apr 14 at 10:22
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You should not be looking at $\ce{-NH-CO\bond{-}}$ as two different functional groups i.e. as $\ce{-NH-}$ and $\ce{-CO-}$.

Since as in $\ce{-(NH-CO)\bond{-}}$: $\ce{N}$'s lone pair are actually in resonance with the carbonyl group.

The left handed phenyl ring is more activated than the right handed phenyl ring. Hence the electrophile would preferentially attack on the left handed phenyl ring.

The amide group is too weak base to be protonated by the acid and therefore it does not direct the electrophile to meta position.

Ortho position is hindered due to steric hindrance of the another phenyl ring.

And therefore

the attack takes place at para position of the left handed phenyl ring

so answer should be option B.

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