ACS question. Need Orgo expert;)

[Innulja]

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Hey guys!
again I need your help here.
In the ACS study guide one of the questions in chapter on Electrophilic Addition, EA-11 has confusing explanation.
the question is:
what is the major product from the reaction of 1-butene with bromine in methanol.

I understand that the reaction proceeds through the bromonium ion however I don't see why the methanol, which acts as a nucleaphile would attack the more substituted carbon. They say that the reason for it would be the more positive partial charge, but isn't it the opposite since the alkyl group is electron releasing and makes it less positive, also wouldn't the sterick hindrance keep it from attacking the more substituted carbon???
Please help me on this one!
thanks to everyone.

 

[wantVCUdental]

i didn't know it would do that, but! after thinking about the product, it makes a little bit of sense.
MeOH is a polar protic solvent, so it favors Sn1 or E1 reaction.
Bromonium ion can fuction like an ether, so think of an ether being in acidic position, the ring opens to leave the cation on secondary carbon. The positive charge is stabilized through solvation by the solvent. And i guess MeOH can go and attack it?
though i thought Br- would go fill that carbocation....

 

[tmac001]

think of it as a carbocation. the more substituted side is more stable (via hyperconjugation) so methanol, which in this case would act as Sn1 attack the more stable carbocation

 

[Innulja]

I understan what you guys are saying, I came to that same conclusion, but I don't understand the explanation they give as to why thay got that answer.
What's even more confusing is the fact that in the ACS book thay teach that the ring opening of epoxides is Sn2, whether it's acid or base catalized, which again make 0 sense to me.
anyone??? Could it be some mistake there?