📖 Theory & Concepts ▼

Acetylation Reaction

Acetylation is the substitution of an acetyl group (CH₃CO-) for an active hydrogen atom in a compound.

Aniline + Acetic Anhydride
↓
Acetanilide + Acetic Acid

Why Acetylate?

  • Protection: Blocks -NH₂ group during other reactions
  • Reduces Basicity: Makes amine less reactive
  • Medicinal: Acetanilide was used as antipyretic (fever reducer)
Product Properties:

White crystalline solid, MP = 114°C, slightly soluble in cold water.

⚗️ Reaction

C₆H₅NH₂
Aniline
+
(CH₃CO)₂O
Acetic Anhydride
→
C₆H₅NHCOCH₃
Acetanilide
+
CH₃COOH
Acetic Acid

Procedure

1. Add aniline (2mL) + Acetic anhydride (3mL)
2. Add zinc dust + glacial acetic acid
3. Reflux for 15 minutes
4. Pour into cold water
5. Filter and recrystallize
Round Bottom Flask
Aniline + Acetic Anhydride
Amber colored mixture

Observations

Begin procedure...
Product Properties:
• White crystalline solid
• Melting point: 113-115°C
• Slightly soluble in cold water