Chapter 21.2, Problem 10CC

(a)

Interpretation Introduction

Interpretation:

The major product of the given transformation has to be predicted.

Concept Introduction:

Hell- Volhard-Zelinsky reaction:

It is the alpha halogenation reaction of carboxylic acid with a bromine molecule and in the presence of ${\text{PBr}}_{\text{3}}$ which is phosphorus tribromide.  The reaction with ${\text{PBr}}_{\text{3}}$ is followed by hydrolysis with a water molecule to end up with the final product.

Example:

(b)

Interpretation Introduction

Interpretation:

The major product of the given transformation has to be predicted.

Concept Introduction:

Hell- Volhard-Zelinsky reaction:

It is the alpha halogenation reaction of carboxylic acid with a bromine molecule and in the presence of ${\text{PBr}}_{\text{3}}$ which is phosphorus tribromide.  The reaction with ${\text{PBr}}_{\text{3}}$ is followed by hydrolysis with a water molecule to end up with the final product.

Example: