Chapter 11, Problem 48P

(a)

Interpretation Introduction

Interpretation:

The product of given reaction should be given.

Concept introduction:

${\text{S}}_{\text{N}}\text{1}$reaction:

In the nucleophilic substitution reaction, the rate of reaction depends only on one reactant, which is involved in reaction is called unimolecular nucleophilic substitution reaction.

In ${\text{S}}_{\text{N}}\text{1}$ reaction, formation of carbocation by reliving of leaving group from reactant is the first step and second step is addition nucleophile to carbocation.

The rate determination step is formation of carbocation.

The stability order of carbocation is,

Tertiary > Secondary > Primary

Therefore, tertiary alcohols undergo substitution very fast than the secondary alcohols because tertiary carbocation is more stable than the secondary carbocation than the primary carbocation. Primary alcohol is less stable therefore it won’t undergoes ${\text{S}}_{\text{N}}\text{1}$ substitution reaction.

${\text{S}}_{\text{N}}2$reaction:

In the nucleophilic substitution reaction, the rate of reaction depends on reactant as well as nucleophile, which are involved in reaction is called bimolecular nucleophilic substitution reaction.

In ${\text{S}}_{\text{N}}2$ reaction, the reliving of leaving group from reactant and nucleophilic of attack takes place simultaneously.

Reactant and nucleophile are present at the rate determination step.

The order of species involving in ${\text{S}}_{\text{N}}2$ reaction is,

Tertiary < Secondary < Primary

Tosylation reaction:

The alcohol is treated with any tosyl chloride (methane sulfonyl chloride) to yields tosylated product, this reaction is called as tosylation and which is shown below,

Answer to Problem 48P

The product is given below,

Explanation of Solution

The given Compound (A) is reaction with methane sulfonyl chloride which gives compound (B). This compound (B) reaction with acetate ion and gives the propyl acetate (D). The reaction is given below,

(b)

Interpretation Introduction

Interpretation:

The product of given reaction should be given.

Concept introduction:

${\text{S}}_{\text{N}}\text{1}$reaction:

In the nucleophilic substitution reaction, the rate of reaction depends only on one reactant, which is involved in reaction is called unimolecular nucleophilic substitution reaction.

In ${\text{S}}_{\text{N}}\text{1}$ reaction, formation of carbocation by reliving of leaving group from reactant is the first step and second step is addition nucleophile to carbocation.

The rate determination step is formation of carbocation.

The stability order of carbocation is,

Tertiary > Secondary > Primary

Therefore, tertiary alcohols undergo substitution very fast than the secondary alcohols because tertiary carbocation is more stable than the secondary carbocation than the primary carbocation. Primary alcohol is less stable therefore it won’t undergoes ${\text{S}}_{\text{N}}\text{1}$ substitution reaction.

${\text{S}}_{\text{N}}2$reaction:

In the nucleophilic substitution reaction, the rate of reaction depends on reactant as well as nucleophile, which are involved in reaction is called bimolecular nucleophilic substitution reaction.

In ${\text{S}}_{\text{N}}2$ reaction, the reliving of leaving group from reactant and nucleophilic of attack takes place simultaneously.

Reactant and nucleophile are present at the rate determination step.

The order of species involving in ${\text{S}}_{\text{N}}2$ reaction is,

Tertiary < Secondary < Primary

This is shown below,

Answer to Problem 48P

The product is given below,

Explanation of Solution

Alcohol (A) is reaction with ${\text{PBr}}_{\text{3}}$ in pyridine which undergoes ${\text{S}}_{\text{N}}\text{2}$ type of reaction, the bromine attacks the carbon atom through the back side and provides brominated compound (C). This is shown below,

(c)

Interpretation Introduction

Interpretation:

The product of given reaction should be given.

Concept introduction:

${\text{S}}_{\text{N}}\text{1}$reaction:

In the nucleophilic substitution reaction, the rate of reaction depends only on one reactant, which is involved in reaction is called unimolecular nucleophilic substitution reaction.

In ${\text{S}}_{\text{N}}\text{1}$ reaction, formation of carbocation by reliving of leaving group from reactant is the first step and second step is addition nucleophile to carbocation.

The rate determination step is formation of carbocation.

The stability order of carbocation is,

Tertiary > Secondary > Primary

Therefore, tertiary alcohols undergo substitution very fast than the secondary alcohols because tertiary carbocation is more stable than the secondary carbocation than the primary carbocation. Primary alcohol is less stable therefore it won’t undergoes ${\text{S}}_{\text{N}}\text{1}$ substitution reaction.

${\text{S}}_{\text{N}}2$reaction:

In the nucleophilic substitution reaction, the rate of reaction depends on reactant as well as nucleophile, which are involved in reaction is called bimolecular nucleophilic substitution reaction.

In ${\text{S}}_{\text{N}}2$ reaction, the reliving of leaving group from reactant and nucleophilic of attack takes place simultaneously.

Reactant and nucleophile are present at the rate determination step.

The order of species involving in ${\text{S}}_{\text{N}}2$ reaction is,

Tertiary < Secondary < Primary

Tosylation reaction:

The alcohol is treated with any tosyl chloride (methane sulfonyl chloride) to yields tosylated product, this reaction is called as alkyl tosylation and which is shown below,

Answer to Problem 48P

The product is given below,

Explanation of Solution

The given Compound (A) is reaction with para toluene sulfonyl chloride which gives compound (B). This compound (B) reaction with phenoxide ion and gives the corresponding ether (D). The reaction is given below,

(d)

Interpretation Introduction

Interpretation:

The product of given reaction should be given.

Concept introduction:

Dehydration reaction:

Removal of water molecule, when the alcohol is treated with strong acid like sulfuric acid is known as dehydration reaction.

The stability of carbocation is given below,

Tertiary carbocation is more stable than the secondary and primary.

Answer to Problem 48P

The product is given below,

Explanation of Solution

The Compound (A) is undergoes dehydration, because the formation of primary carbocation and it is less stable which forms secondary carbocation and the hydrogen is removed from adjacent β- carbon atom which leads to the formation of alkene (B).

(e)

Interpretation Introduction

Interpretation:

The product of given reaction should be given.

Concept introduction:

In the presence of acid catalyst, this reaction takes place through partial ${\text{S}}_{\text{N}}\text{1}$ and partial ${\text{S}}_{\text{N}}\text{2}$ pathway. Epoxides are reactive, Epoxides get protonated followed by alcohol attacks to the stable carbocation and form the product.

Epoxides are reactive, methoxide ion attacks Epoxides in a less sterically hindered position which forms the alkoxide ion, and then it gets proton from alcohol which form the product.

Answer to Problem 48P

The product is given below,

Explanation of Solution

The reaction is shown below,

Epoxides are reactive, methoxide ion attacks the Epoxides (A) in a less sterically hindered position which forms the alkoxide ion (B), then it gets proton from alcohol which form the product (C). Therefore the major product is shown above.

(f)

Interpretation Introduction

Interpretation:

The product of given reaction should be given.

Concept introduction:

In the presence of acid catalyst, this reaction takes place through partial ${\text{S}}_{\text{N}}1$ and partial ${\text{S}}_{\text{N}}2$ pathway. Epoxides are reactive, Epoxides get protonated followed by alcohol attacks to the stable carbocation and form the product.

Epoxides are reactive, methoxide ion attacks theEpoxides in a less sterically hindered position which forms the alkoxide ion, and then it gets proton from alcohol which form the product.

Answer to Problem 48P

The product is given below,

Explanation of Solution

The reaction is shown below,

In the presence of acid catalyst, this reaction takes place through partial ${\text{S}}_{\text{N}}1$ and partial ${\text{S}}_{\text{N}}2$ pathway. Epoxides are reactive Epoxides (A) get protonated forms compound (B) followed by alcohol attacks to the stable carbocation and form the final product (C).

(g)

Interpretation Introduction

Interpretation:

The product of given reaction should be given.

Concept introduction:

${\text{S}}_{\text{N}}\text{1}$reaction:

In the nucleophilic substitution reaction, the rate of reaction depends only on one reactant, which is involved in reaction is called unimolecular nucleophilic substitution reaction.

In ${\text{S}}_{\text{N}}\text{1}$ reaction, formation of carbocation by reliving of leaving group from reactant is the first step and second step is addition nucleophile to carbocation.

The rate determination step is formation of carbocation.

The stability order of carbocation is,

Tertiary > Secondary > Primary

Therefore, tertiary alcohols undergo substitution very fast than the secondary alcohols because tertiary carbocation is more stable than the secondary carbocation than the primary carbocation. Primary alcohol is less stable therefore it won’t undergoes ${\text{S}}_{\text{N}}\text{1}$ substitution reaction.

${\text{S}}_{\text{N}}2$reaction:

In the nucleophilic substitution reaction, the rate of reaction depends on reactant as well as nucleophile, which are involved in reaction is called bimolecular nucleophilic substitution reaction.

In ${\text{S}}_{\text{N}}2$ reaction, the reliving of leaving group from reactant and nucleophilic of attack takes place simultaneously.

Reactant and nucleophile are present at the rate determination step.

The order of species involving in ${\text{S}}_{\text{N}}2$ reaction is,

Tertiary < Secondary < Primary

Chlorination reaction:

The alcohol is treated with thionyl chloride to yields chlorinated product, this reaction is called as chlorination and which is shown below,

Answer to Problem 48P

The product is given below,

Explanation of Solution

The given Compound (A) is reaction with thionyl chloride which gives compound (B). This compound (B) reaction with chlorine ion and gives the corresponding chloro compound (C). The reaction is given below,