Chemistry Reference
In-Depth Information
secondary carbocation or a less stable primary carbocation. When bromide adds to
the tertiary carbocation, a second alkyl bromide is formed.
Like Problems 2(b) and 2(c), this is also a solvolysis reaction. However, due to the
increased complexity of the starting compound, the potential product mixture is more
complex. Specifically, if we consider the initial solvolysis step and elimination of
water, we notice that an allyl carbocation is formed that is adjacent to a migratable
hydrogen atom. While reaction of this carbocation with bromide generates a second-
ary allyl bromide, a 1,2-hydride shift followed by reaction with bromide generates a
tertiary bromide. Alternatively, if the positive charge migrates through the double
bond (see arrow pushing), an allylic carbocation adjacent to a tert-butyl group
results. Reaction of this carbocation with bromide generates a new allyl bromide.
However, if a 1,2-alkyl shift occurs, the resulting tertiary carbocation can react
with bromide to form a new tertiary bromide.
