[malonicman]

Yesterday, I came across a problem involving the reaction of HCl with 3-methylcyclopentene to yield 3-bromo-3-methylcyclopentene.  It requests a reasonable mechanism for said reaction.  I'm at quite a loss, as I am only familiar with the mechanism for the reaction yielding 3-bromo-3-methylcyclopentane by electrophilic addition with a hydride shift.  Any hints or suggestions?

Thanks

[ooosh]

I don't know how can you get bromide by using hydrogen chloride.

[malonicman]

Yesterday, I came across a problem involving the reaction of HCl with 3-methylcyclopentene to yield 3-chloro-3-methylcyclopentene.  It requests a reasonable mechanism for said reaction.  I'm at quite a loss, as I am only familiar with the mechanism for the reaction yielding 3-chloro-3-methylcyclopentane by electrophilic addition with a hydride shift.  Any hints or suggestions?

Thanks

I meant to write "chloro."

[plankk]

If we talk about chlorine derivatives, the NCS should do everything what you want (look for Wohl-Ziegler Reaction, it is exactly a reaction with NBS but NCS should work exactly in the same way).

[Doc Oc]

If that's all the information you're given then it sounds like a typo.  Check w/the prof.

[orgopete]

That looks like a pretty generic example of an electrophilic addition of HCl (protonation of the double bond), rearrangement to the more stable carbocation, and addition of chloride to the more stable carbocation. It isn't a chlorination reaction.

[malonicman]

I checked with grad students who had worked on the same problem set last year, and indeed it is an error.  I was driving myself mad over nothing!!!

Thanks.