Chapter 11, Problem 11.53P

Interpretation Introduction

(a)

Interpretation:

How the given transformation can be carried out is to be shown.

Concept introduction:

An alkene can be transformed into its constitutional isomer through a series of reactions. This generally involves the electrophilic addition, of a Bronsted acid such as HBr to the alkene followed by an elimination of HBr. Another possibility is the addition of a weak acid like ${\text{H}}_{\text{2}}\text{O}$ in the presence of a strong acid. The choice of the electrophilic addition reaction and the choice of the second stage elimination reaction depends on the nature of the starting alkene and the desired product, particularly the type of carbocation that will form during addition as well as during the second stage elimination. If the formation and rearrangement of a carbocation are needed for shifting the position of the double bond, the elimination must be an E1 reaction.

Interpretation Introduction

(b)

Interpretation:

How the given transformation can be carried out is to be shown.

Concept introduction:

An alkene can be transformed into its constitutional isomer through a series of reactions. This generally involves the electrophilic addition, of a Bronsted acid such as HBr to the alkene followed by an elimination of HBr. Another possibility is the addition of a weak acid like ${\text{H}}_{\text{2}}\text{O}$ in the presence of a strong acid. The choice of the electrophilic addition reaction and the choice of the second stage elimination reaction depends on the nature of the starting alkene and the desired product, particularly the type of carbocation that will form during addition as well as during the second stage elimination. If the formation and rearrangement of a carbocation are needed for shifting the position of the double bond, the elimination must be an E1 reaction.