Chapter 18.12, Problem 25CC

(a)

Interpretation Introduction

Interpretation:

The products obtained when benzene is treated with the following reagents have to be identified.

Fuming Sulfuric acid

Concept Introduction:

Electrophilic substitution reaction is a type of reaction in which a particular group or atom in a compound is replaced by electrophile. An electrophile is an species that is deficient of electrons.

Sulfonation of benzene is a type of electrophilic substitution reaction in which one of the six Hydrogen atoms in benzene is substituted by ${\text{-SO}}_{\text{3}}\text{H}$ group.

(b)

Interpretation Introduction

Interpretation:

The products obtained when benzene is treated with the following reagents have to be identified.

${\text{HNO}}_{\text{3}}{\text{/H}}_{\text{2}}{\text{SO}}_{\text{4}}$

Concept Introduction:

Electrophilic substitution reaction is a type of reaction in which a particular group or atom in a compound is replaced by electrophile. An electrophile is an species that is deficient of electrons.

Nitration  of  benzene is known as inserting ${\text{-NO}}_2$ group into the benzene Carbon by replacing one of its Hydrogen atoms.

(c)

Interpretation Introduction

Interpretation:

The products obtained when benzene is treated with the following reagents have to be identified.

${\text{Cl}}_{\text{2}}{\text{/AlCl}}_{\text{3}}$

Concept Introduction:

• Benzene and its related compounds undergo aromatic electrophilic substitution reactions. An electrophile is known as electron deficient species.

• Chlorination of  benzene is inserting $\text{-Cl}$ group in the ring by replacing one of its Hydrogen atoms.

(d)

Interpretation Introduction

Interpretation:

The products obtained when benzene is treated with the following reagents have to be identified.

Ethyl chloride, ${\text{AlCl}}_{\text{3}}$

Concept Introduction:

• Benzene and its related compounds undergo aromatic electrophilic substitution reactions. An electrophile is known as electron deficient species.

• Friedel Crafts reaction is an electrophilic substitution reaction. This reaction involves $\text{C-C}$ bond formation between benzene Carbon and any other alkyl or aryl or acyl carbon. Thus this reaction is constructive to impart alkyl, aryl or acyl group onto benzene ring. So this reaction is commonly known as Friedel Crafts acylation if acyl group is imparted on benzene ring or Friedel Crafts alkylation if alkyl group is imparted on benzene ring.

(e)

Interpretation Introduction

Interpretation:

The products obtained when benzene is treated with the following reagents have to be identified.

${\text{Br}}_{\text{2}}$, $\text{Fe}$

Concept Introduction:

Electrophilic substitution reaction is a type of reaction in which a particular group or atom in a compound is replaced by electrophile. An electrophile is an species that is deficient of electrons.

Bromination  of  benzene is known as inserting $\text{Br}$ group into the benzene Carbon by replacing one of its Hydrogen atoms.

(f)

Interpretation Introduction

Interpretation:

The products obtained when benzene is treated with the following reagents have to be identified.

${\text{HNO}}_{\text{3}}{\text{/H}}_{\text{2}}{\text{SO}}_{\text{4}}$ followed by $\text{Zn/HCl}$

Concept Introduction:

• Benzene and its related compounds undergo aromatic electrophilic substitution reactions. An electrophile is known as electron deficient species.

• Nitration  of  benzene is known as inserting ${\text{-NO}}_2$ group into the benzene Carbon by replacing one of its Hydrogen atoms.

• Reduction of Nitro group by various reagents such as Sodium sulfide, Sodium hydrosulfite, Tin(II) chloride, $\text{Zn/HCl}$ etc convert nitro group to amino group.

Answer:

Benzene when reacts with ${\text{HNO}}_{\text{3}}{\text{/H}}_{\text{2}}{\text{SO}}_{\text{4}}$ followed by $\text{Zn/HCl}$

When Benzene reacts with ${\text{HNO}}_{\text{3}}{\text{/H}}_{\text{2}}{\text{SO}}_{\text{4}}$ followed by $\text{Zn/HCl}$ Aniline is formed.