[KurzickMushroom]

Hi, my teacher said something about this that I did not agree with. When adding any acid, HX, to an alkene, Markovnikov's rule applies. The except to this is HBr. If HBr is added, anti-Mark's applies. My teacher told me anti Mark's rule applies only in the presence of Sulfuric Acid as a catalyst. I search on multiple websites and asked my tutor. H2SO4 is never mention as a catalyst.

Is this true? ( Does anti-Mark's rule apply only if HBr is in the presence of Sulfuric Acid?
Is H2SO4 needed as a catalyst for all Mark rule applications?

Thanks in advance.

[JGK]

My old texbook and the site listed below indicate that it is pthe presence or absence of peroxides which determine where the Br binds.

http://www.chemguide.co.uk/mechanisms/freerad/alkenehbr.html

Anti Markovnikov occurs in the presence of peroxides (also called the "peroxide effect")

[KurzickMushroom]

aww damn it! Thank you very much for the quick reply.