Question

Aromatic substitution by amine.

Answer 1

The question is... "Use curved arrows to show the mechanism for the following reactions:"

What I've got is this:

The reactants and products are what the question asks for, but I'm unsure about the intermediate steps.

I'm unsure how the quaternary salt turns into a tertiary amine. My best guess was that bromide ion will pull the hydrogen from the nitrogen, but that doesn't make much sense since hydrogen bromide is extremely acidic.

Answer 2

I agree this mechanism, I mean addition-elimination versus benzyne.
your mechanism is totally true but there are several other resonance forms that don't matter.

for more information you can see this book:
Fundamentals of organic reactions mechanism by J, Harris.