[Enola]

Hi,
I have a question about reaction:

benzene + 1-bromo-2-methylpropane in the presence of FeBr₃

What will be the main product? tert-Butylbenzene or Isobutylbenzene?

[Babcock_Hall]

What do you think, and what is your reasoning?  It is a forum rule (see red link above) that you must provide your attempt at solving a problem before we can help you.

[Enola]

Well,
at first I was thinking about Isobutylbenzene because it seems like a easy reaction. But my friend told me that tert-Butylbenzene is the right anwer because of carbocation (tertiary is more stable) and now I'm confused. It seems odd to me but at the same time I'm really not sure what is the right answer ...

[Babcock_Hall]

Think about how one carbocation can rearrange to form another carbocation.

[Enola]

In that case it looks like it can't. There are only single bonds and carbon atom cannot just take away hydrogen from another carbon ... Am I right or am I missing something?

[AWK]

http://www.chemhelper.com/friedelcrafts.html

[Enola]

Thank you very much!

[Babcock_Hall]

In general a carbocation can rearrange to another, more stable carbocation via a hydride shift or a methide shift.  A hydride ion is a hydrogen nucleus with two electrons, and it has a formal charge of minus one.  You might try writing out the mechanism of a rearrangement for practice.