Question

How does an arenium ion's resonance structure show us that it favors either ortho/para or meta directing?

@Somy

Answer 1

idk u explain lol ♥

Answer 2

While I prepare, try to draw the mechanism of the reaction of aniline with AlCl3 and Cl2. I'm going to take a while to explain the mechanism behind the reaction so that you can work it out. I think being able to work out organic chemistry problems kind of like math problems is the best way. If this doesn't make sense, hopefully it will very soon!

Answer 3

You have two options. We can do the full mechanism for this reaction or we can simplify it so that we assume that AlCl3 and Cl2 really just puts Cl+ into solution for the aromatic ring to act as an electrophile.

Answer 4

AlCl3 +Cl2 --> im kinda confused

Answer 5

ohhh we put them into benzene ring?

Answer 6

oh ok i didn't know whats aniline

Answer 7

Wait, I'm sorry I just realized that I made this reaction up on the spot, and doing the exact reaction I describe will fail.

Aniline is the common name for aminobenzene.

Answer 8

Alright, now the problem with adding chlorine through using AlCl3 and Cl2 is that we'll instead make a salt that interacts with the lone electron pair on the nitrogen. So we're going to have to pick something else. In general what you might want to do is reduce a nitro group to an amine group. Which you can use metal and an acid.

So instead lets start out with something else, I feel like I've needlessly confused you haha we'll do a better example.

Nitrobenzene will be our starting compound and we'll react it with AlCl3 and Cl2 to add.

Answer 9

AlCl3 and Cl2
this reaction would be substitution right?

Answer 10

Yes, although it's not exactly a normal substitution as we'll see. It's not quite SN2 or SN1, instead we call it "Electrophilic aromatic substitution" and this is the subject of the lesson today. How does this substitution happen?

Answer 11

hmmm electrophilic
that would mean electron wanting

Answer 12

so that means something that we are going to add has to want an electron
and the benzene ring has to have that electron to donate

Answer 13

Yep exactly. To test your knowledge, finish drawing the formal charges and bonds and electron pairs on the nitro group of nitrobenzene.

Answer 14

hmmm