Chapter 18, Problem 81IP

 (a)

Interpretation Introduction

Interpretation:

• The given following compounds have to be designed using other reagents.

 Concept Introduction:

• Electrophiles are electron deficient species. In Electrophilic substitution reaction a group or atom in a compound is replaced by electrophile. This kind of reaction occurs predominantly in aromatic compounds. Electrophilic substitution reactions of aromatic compounds are known as aromatic electrophilic substitution reactions.

• Benzene is an electron rich Aromatic compound. It undergoes aromatic electrophilic substitution reaction. 

• The delocalized nature of pi electrons in benzene attributes a special property to benzene called resonance.

• If the substituents on benzene Carbon are Electron rich groups they are known as activating groups. They are ortho- and para- directing groups because these groups when directly bonded to benzene Carbon increases the electron density at ortho and para positions. So they direct the incoming electrophile towards ortho and para position in electrophilic substitution reactions.

• If the substituents on benzene Carbon are Electron withdrawing groups they are known as deactivating groups. They are meta-directing groups because these groups when directly bonded to benzene Carbon decreases the electron density at ortho and para positions and so the incoming electrophile is directed towards meta position.

• Friedel-Crafts Alkylation: This Lewis acid-catalyzed electrophilic aromatic replacement allows the synthesis of alkylated products by means of the reaction of arenes through alkyl halides or alkenes.
• Friedel-Crafts Acylation: This electrophilic aromatic substitution allows the synthesis of monoacylated yield from the reaction stuck between arenes and acyl chlorides or anhydrides. The products are deactivated, as well as do not undergo a second substitution.

(b)

Interpretation Introduction

Interpretation:

The given following compounds have to be designed using other reagents.

Concept Introduction:

• Electrophiles are electron deficient species. In Electrophilic substitution reaction a group or atom in a compound is replaced by electrophile. This kind of reaction occurs predominantly in aromatic compounds. Electrophilic substitution reactions of aromatic compounds are known as aromatic electrophilic substitution reactions.

• Benzene is an electron rich Aromatic compound. It undergoes aromatic electrophilic substitution reaction. 

• The delocalized nature of pi electrons in benzene attributes a special property to benzene called resonance.

• If the substituents on benzene Carbon are Electron rich groups they are known as activating groups. They are ortho- and para- directing groups because these groups when directly bonded to benzene Carbon increases the electron density at ortho and para positions. So they direct the incoming electrophile towards ortho and para position in electrophilic substitution reactions.

• If the substituents on benzene Carbon are Electron withdrawing groups they are known as deactivating groups. They are meta-directing groups because these groups when directly bonded to benzene Carbon decreases the electron density at ortho and para positions and so the incoming electrophile is directed towards meta position.

• Friedel-Crafts Alkylation: This Lewis acid-catalyzed electrophilic aromatic replacement allows the synthesis of alkylated products by means of the reaction of arenes through alkyl halides or alkenes.
• Friedel-Crafts Acylation: This electrophilic aromatic substitution allows the synthesis of monoacylated yield from the reaction stuck between arenes and acyl chlorides or anhydrides. The products are deactivated, as well as do not undergo a second substitution.