Acetanilide synthesis

Synthesis of Acetanilide from Aniline

1. Objective: Preparation of Acetanilide from Aniline . Mrs Chanda Ranjan Dept of Pharm Chemistry The Oxford College of Pharmacy

2. Objective: Preparation of Acetanilide from Aspirin Chemicals Required: Aspirin, acetic anhydride, sodium acetate, conc hydrochloric acid, water and methylated spirit. Apparatus Required: Beaker, conical flask, funnel, stirrer, and pipette.

3. Principle: Acetanilide  is an odorless solid chemical of leaf or flake-like appearance. Acetanilide was the first  aniline  derivative found to possess analgesic  as well as antipyretic properties. Acetanilide is prepared by acetylation of aniline with acetic anhydride and in the presence of sodium acetate and hydrochloric acid . The active hydrogen atom present in the amino group is replaced by the by the acetyl group of acetic anhydride in the presence of sodium acetate and forms Acetanilide. Reaction Involved

4. Mechanism Involved Principle: Acetanilide is prepared by acetylation of aniline with acetic anhydride and in the presence of sodium acetate and hydrochloric acid. The active hydrogen atom present in the amino group is replaced by the by the acetyl group in the presence of sodium acetate and forms Acetanilide.

5. 1. About 4 ml of Aniline was taken and added to 3.7 ml of conc HCl dissolved in 100 ml of water 4 ml of Aniline 3.7 ml conc HCl + 100 ml of water 2. The mixture is stirred until a clear solution is obtained. Procedure Stir well to get a clear solution

6. 3. To the clear solution 5.3 ml of acetic anhydride was added and stirred. 5.3 ml of acetic anhydride 5.7 gm sodium acetate dissolved in 20 ml of water 4. Then a crystalline sodium acetate (5.7 gm.) in water 20 ml was also added and stirred . Procedure Stirred well

7. Ice cubes are added Stir well 5. To the mixture ice was added to it and stirred vigorously 6. Acetanilide was separated Procedure

8. The precipitate obtained of acetanilide is filtered 7. Acetanilide was filtered. Procedure cold water 8. The obtained acetanilide was washed with cold water.

9. crystallized with boiling water containing 2-5 ml methylated sprit Crude Acetanilide 9. Crystallized with cold water containing methylated spirit (10 % methanol ). Procedure 10. The obtained compound will be weighed and melting point will be determined and practical yield will be calculated.

10. Calculation Molecular weight of Aniline= 93 gm ( 1.02  g/cm³)=91.176 ml Molecular weight of Acetanilide= 135 gm 91.176ml of Aniline gives---  135 gm of Acetanilide Therefore, 4 ml of Aniline will give---- 5.92 gm of Acetanilide (theoretically) Percentage yield= Practical Yield x 100 --------------------- Theoretical yield

11. Thank You