Synthesis of Acetanilide from Aniline

Acetanilide

Acetanilide from aniline mechanism, preparation of acetanilide from aniline practical pdf, synthesis of acetanilide from aniline and acetyl chloride, why glacial acetic acid is used in preparation of acetanilide from aniline, theoretical yield of acetanilide from aniline

BACKGROUND

Principle:

Acetanilide is synthesized from aniline by acetylating it with acetic anhydride in presence of glacial acetic acid. Aniline or phenylamine is a primary amine and basic in nature. Acetic anhydride, an anhydride of acetic acid, acts as a source of acyl group here .

Telegram	Subscribe
Facebook	Follow
Website	Click here

Aniline reacts with acetic anhydride to form Acetanilide by nucleophilic substitution reaction and the reaction is called acetylation. In this reaction, aniline acts as the nuclepohile and acyl (CH₃CO-) group from acetic anhydride acts as the electrophile. Here, the hydrogen atom of –NH₂ group is replaced by the acyl group.¹

Aim: To prepare acetanilide from aniline.

Reaction:

Mechanism:

Use:

It is an antipyretic agent.

REQUIREMENTS

Chemicals:     

• Acetic acid/anhydride mixture – 20 ml
• Aniline – 10 ml

Apparatus:     

• Conical flask – 250 ml
• Reflux water-condenser set
• Buchner funnel
• Measuring cylinder
• Filter paper

PROCEDURE

Add 20 ml of a mixture of acetic anhydride and glacial acetic acid (equal volumes) to 10 ml (10.3 g) of aniline in a conical flask of 250 ml. Fit a reflux water-condenser to the flask and gently boil the mixture for 10 min. Then pour the hot liquid into 200 ml of cold water with constant stirring.

The acetanilide quickly crystallises. Filter yield by a pump and wash the crude acetanilide well with water.

Recrystallise from about 60 ml of a mixture of one volume of acetic acid and two volumes of water: filter off the colourless crystals at the pump, again wash thoroughly with water, drain and dry.

Note:

Alternatively, the crude acetanilide may be recrystallised from boiling water, but in this case a much greater volume (about 300 ml) of the solvent will be required.

Calculation:

Here limiting reagent is aniline; hence yield should be calculated from its amount taken.

Molecular formula of aniline = C₆H₇N₁

And molecular formula of acetanilide = C₈H₉O₁N₁

Molecular weight of aniline = 93 g/mole

And molecular weight of acetanilide = 135 g/mole

Theoretical yield:

1 g aniline forms 135 g acetanilide

Therefore, 10.3 g (10 ml) aniline will form ………? (X) g acetanilide

X =( 135 × 10.3)/93 = 14.95 g

Theoretical yield = 14.95 g

Practical yield = ————- g

% Yield = (Practical Yield)/(Theoretical Yield) × 100

CONCLUSION

Acetanilide was synthesized and the percentage yield was found to be………..% (M.p. 113°; yield, 10 g.).

REFERENCES

1. Practical Organic Chemistry by Frederick George Mann and Bernard Charles Saunders Published by Longan Inc., Fourth Edition; Page No. 108.

Also read:

• Synthesis of Phenytoin from Benzil and Urea
• Synthesis of anthranilic acid from phthalic anhydride
• Synthesis of aspirin from salicylic acid using acetic anhydride
• Synthesis of aspirin from salicylic acid using acetyl chloride and pyridine
• Synthesis of paracetamol from p-aminophenol
• Synthesis of acetaminophen (paracetamol) from p- aminophenol by using microwave system
• Synthesis of p-nitroaniline from acetanilide
• Synthesis of p-aminophenol from nitrobenzene

🔴 Would you like to attempt Labmonk Daily quiz? Click here

🔵 Check out Jobs & Exam Notices. Labmonk Notice Board

🔴 Labmonk Scholarships. Click here

🔵 Labmonk Blog. Click here

🔴 Do you need notes? Click here

Watch Career related videos on Youtube: Watch now !!

FAQs