Please heellppppppppp!!!!

Question

How do you expect the following series of compounds to compare in behavior in the two tests?(Sn1/Sn2 reaction)

CH3-CH=CH-CH2-Br CH3-C=CH-CH3
!
Br
CH3-CH2-CH2-CH2-Br

Please help me answer this question, I really don't understand and don't know how to answer this question. Thanks.

Answer 1

You might want to look at http://en.wikipedia.org/wiki/SN1_reaction and the similar page for SN2.

You are looking for how stable is the carbocation that is formed, the more stable the more likely that the reaction is SN1 rather than SN2.

so which is the more stable?

CH3-CH=CH-CH2+

CH3-C=C(+)H-CH3

CH3-CH2-CH2-CH2+

There is also the question which carbocation is also likely to rearrange?