Ortho/Para Director?

[victorias]

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Why is A not the answer?

CH3 is an ortho/para director so shouldn't it be that the nitro group will end up in the 2 ortho and 1 para position, giving a total of 3 possible positions.

I know that the 5 hydrogens can be replaced with nitrogen but don't we have to take into account if there is a an EDG or EWG already on the benzene ring?

 

[victorias]

Does it mean that some nitro group could be added onto the meta position in the presence of an electron donating group but that it is less likely than having it at the ortho/para positions?


Why exactly does an electron donating group is ortho/para directing?

 

[Cawolf]

You are overthinking the question, as directing groups don't limit substitution to certain spots. They simply make it thermodynamically more likely for a substitution to occur at a given hydrogen. The energy barrier may be high to form pentanitrotoluene, but it can exist, and that is what the question is asking.

Does it mean that some nitro group could be added onto the meta position in the presence of an electron donating group but that it is less likely than having it at the ortho/para positions?

Yes, it is just more thermodynamically favorable for ortho/para substitution to occur. With enough energy, you could substitute at any position.

Why exactly does an electron donating group is ortho/para directing?

It comes down to electron density through resonance structures (and inductive effects) that influence the electronics of the substitution reaction. Consider that a methyl group slightly donates electrons to the proximal benzene carbon, giving it a partial negative charge. If you draw the resonance structures, you will see that this negative charge is spread over the ortho and para positions. That makes the ortho and para positions a more favorable site for electrophilic aromatic substitution.