Destroyer 2011 OC #55

[dents1]

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Shouldn't the NO2 be added meta since its electron withdrawing? I understand that when Sn,HCl and OH- are added the NO2 becomes NH2 which is electron donating which is ortho/para. But the NO2 should be placed meta therefore the NH2 should be meta.
Hopefully I explained myself clearly.
Clarification would be greatly appreciated.
Thanks!

 

[radmazindds]

NO2 is added para because the alkyl group is O/P directing. The 1. Sn/HCl, 2. OH- acts to reduce the NO2 to NH2.

it doesn't matter how the group you're adding is directing. It matters how the substituents already on the molecule are directing.

Shouldn't the NO2 be added meta since its electron withdrawing? I understand that when Sn,HCl and OH- are added the NO2 becomes NH2 which is electron donating which is ortho/para. But the NO2 should be placed meta therefore the NH2 should be meta.
Hopefully I explained myself clearly.
Clarification would be greatly appreciated.
Thanks!

 

[PooyaH]

Whenever you're adding something to the benzene, you only need to look at what is already on the benzene! In this case, an alkane (butane) is already attached to the benzene which is electron donating/activating. And as we know, electron donating/activating groups promote para/ortho addition*.

Now let's say if the NO2 was first on the benzene and you were to add the alkane, then you would add it meta since NO2 is electron withdrawing/deactivating.

Edit: *I guess I should've said electrophilic substitution instead of addition.

 

[dents1]

Great, thanks guys!