[Cooper]

Hi,

My textbook says that nitration of toluene yields NO₂ on the ortho position relative to the methyl in the major product.

Why is this so? Why is the major product o-nitrotoluene and not p-nitrotoluene?

Thanks!

[Guitarmaniac86]

Have you read about the directing effects of other substituents?

The methyl group on the benzene ring is a ortho para directing substituent. If you draw the resonance structures of the intermediate you will see something that may explain why the ortho substituent is the major product.

[408]

Your textbook is wrong.
Ortho is only the slightly predominant product, para is significant as well.  60:40 or so.
http://www.thecatalyst.org/experiments/AndersonS/AndersonS.html

[pigeonsATW]

I think this is the reason...
Methyl while being a deactivator is Ortho and para directing. There being two ortho positions and only one para position makes the ortho position the major product. I would expect the product to be  65% ortho and 35% para.
I'm also assuming that Methyl is not a big enough group to cause steric hindrance.

[Cooper]

I think this is the reason...
Methyl while being a deactivator is Ortho and para directing. There being two ortho positions and only one para position makes the ortho position the major product. I would expect the product to be  65% ortho and 35% para.
I'm also assuming that Methyl is not a big enough group to cause steric hindrance.

Ah, that makes sense, the methyl is probably too small to hinder the oncoming substituent.

P.S. I assume that you meant methyl was an activator, right?

Thanks everyone

[pigeonsATW]

Yeah, activator... for some reason I got CH₃ confused with Cl.