Chapter 12, Problem 12.50P

Interpretation Introduction

(a)

Interpretation: The alkene or alkyne which yields the given oxidative cleavage products is to be predicted.

Concept introduction: In presence of ozone and $\text{Zn},{\text{H}}_{\text{2}}\text{O}$, oxidative cleavage occurs. In oxidative cleavage both the sigma and pi bond of the alkene is broken and two carbonyl compounds are formed. Aldehydes or ketones are formed depending upon substituents. When ozone is added to the alkene, unstable intermediate molozonide is formed which rearranges to ozonide. This ozonide is reduced to form two carbonyl compounds in presence of $\text{Zn},{\text{H}}_{\text{2}}\text{O}$.

Interpretation Introduction

(b)

Interpretation: The alkene or alkyne which yields the given oxidative cleavage products is to be predicted.

Concept introduction: In presence of ozone and $\text{Zn},{\text{H}}_{\text{2}}\text{O}$, oxidative cleavage occurs. In oxidative cleavage both the sigma and pi bond of the alkene is broken and two carbonyl compounds are formed. Aldehydes or ketones are formed depending upon substituents. When ozone is added to the alkene, unstable intermediate molozonide is formed which rearranges to ozonide. This ozonide is reduced to form two carbonyl compounds in presence of $\text{Zn},{\text{H}}_{\text{2}}\text{O}$.

Interpretation Introduction

(c)

Interpretation: The alkene or alkyne which yields the given oxidative cleavage products is to be predicted.

Concept introduction: In presence of ozone and ${\text{H}}_{\text{2}}\text{O}$, oxidative cleavage occurs in alkynes. In oxidative cleavage both the sigma and pi bonds of the alkyne is broken. In case of terminal alkynes, carboxylic acid and carbon dioxide is formed while in case of internal alkynes, only carboxylic acids are formed.

Interpretation Introduction

(d)

Interpretation: The alkene or alkyne which yields the given oxidative cleavage products is to be predicted.

Concept introduction: In presence of ozone and ${\text{H}}_{\text{2}}\text{O}$, oxidative cleavage occurs in alkynes. In oxidative cleavage both the sigma and pi bonds of the alkyne is broken. In case of terminal alkynes, carboxylic acid and carbon dioxide is formed while in case of internal alkynes, only carboxylic acids are formed.