Chapter 10, Problem 10.72P

Interpretation Introduction

(a)

Interpretation: The product(s) formed by the reaction of $E$ isomer of ${\text{C}}_{\text{6}}{\text{H}}_{\text{5}}\text{CH}={\text{CHC}}_{\text{6}}{\text{H}}_{\text{5}}$ with ${\text{Br}}_{\text{2}}$, followed by one equivalent of $\text{KOH}$ is to be predicted. The resulting alkenes are to be labeled as $E$ or $Z$.

Concept introduction: The general steps involved in the addition of halogens to alkenes are stated below:

• The first step is the electrophilic attack of halide ion to form a halonium ion.

• The second step is the attack of halide ion from back side to open the halonium ion.

Interpretation Introduction

(b)

Interpretation: The product(s) formed by the reaction of $Z$ isomer of ${\text{C}}_{\text{6}}{\text{H}}_{\text{5}}\text{CH}={\text{CHC}}_{\text{6}}{\text{H}}_{\text{5}}$ with ${\text{Br}}_{\text{2}}$, followed by one equivalent of $\text{KOH}$ is to be predicted.

Concept introduction: The general steps involved in the addition of halogens to alkenes are stated below:

• The first step is the electrophilic attack of halide ion to form a halonium ion.

• The second step is the attack of halide ion from back side to opens the halonium ion.

Interpretation Introduction

(c)

Interpretation: The relation between the two compounds formed in part (a) and (b) are to be stated.

Concept introduction: Diastereomers compounds are not mirror images of each other and are different in configuration at one or more stereocentres.

The isomers which have same molecular formula but different connectivity of atoms are constitutional isomers.