Question

What is the action of the following reagents on aniline?
Acetic anhydride.

Answer 1

Hint: Acetic anhydride reacts with compounds and forms acetyl derivative of the respective compound. The reaction of acetic anhydride with highly reactive compounds and formation of acetylated products is called acylation or acetylation.

Complete step by step answer:
- The acetic anhydride reacts with aniline, the reaction is known as ethanoylation or acetylation reaction, which produces a product which is named as acetanilide and acetic acid is another product.
- Acetic anhydride, or ethanoic anhydride, is the chemical compound with the formula $${(C{H}_{3}CO)}_{2}O$$ and it is commonly abbreviated as $$A{C}_{2}O$$.
- Acetic anhydride is the modest isolable anhydride of a carboxylic acid and is extensively used as a reagent in organic synthesis.

- The above reaction is a substitution reaction, replaces hydrogen from aniline with acetyl group and comes under $$S{N}^2$$.
- The acetylation of aniline generally takes place in the presence of Zinc dust.
- Zinc dust is used in the chemical reaction to prevent the oxidation of aniline.
- Acetanilide is very important and it is used as a medicine (febrifuge).

Note: Don’t be confused with the words acetylation, acylation, and ethanoylation. All three words are the same.
Acetylation: Acetylation is a chemical reaction and also called ethanoylation. It describes a reaction that introduces an acetyl functional group into the desired chemical compound. $${(C{H}_{3}CO)}_{2}O$$is commonly used in acetylation.
$${(C{H}_{3}CO)}_{2}O$$-acetic anhydride.

- Aniline.

-Acetanilide.
$$C{H}_{3}COOH$$ - Acetic acid.