O chem question

[Scott Davis]

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When reacting a cyclohexane, containing one methanol group attached to the ring, with PBr3, why does the Bromine attached in an anti-Mark way. I'm used to the reactant being HBr or Br2 among other things. Or PBr3 being used to add a Br to a carbonyl of a carboxylic acid. I don't really understand the chemistry behind the movement i guess.

 

[aqz]

Uh.

Cyclohexanol + PBr3 -> 1-bromo-cyclohexane

Don't see where the markovnikov comes into play.

 

[412smb412]

When reacting a cyclohexane, containing one methanol group attached to the ring, with PBr3, why does the Bromine attached in an anti-Mark way. I'm used to the reactant being HBr or Br2 among other things. Or PBr3 being used to add a Br to a carbonyl of a carboxylic acid. I don't really understand the chemistry behind the movement i guess.

SN2 rxn in case ur wondering but don't wry bout mechanism

 

[Msmouth]

Markovnikov only applies to alkenes and adding to the less substituted side of a double bond. Was your reactant a cyclohexane or cyclohexene?

 

[Msmouth]

SN2 rxn in case ur wondering but don't wry bout mechanism

If it is SN2, you have will have complete inversion. Is that what your asking?

 

[Scott Davis]

Okay thanks. It was from a destroyer question. I shouldn't have used "anti-mark", sorry for the confusion. I see the SN2 reaction now. With SN1's and SN2's I'm usually able to mentally see the reaction take place, PBr3 just kinda through me off a bit.