(a) Acetylation of one of the following compounds: phenols (β-naphthol, vanillin, salicylic acid) by any one method: Using conventional method or using green approach.

Acetylation is a chemical reaction that introduces an acetyl group (CH₃CO) into a compound. In this question, we will discuss the acetylation of phenolic compounds such as β-naphthol, vanillin, or salicylic acid.
Acetylation can be accomplished through conventional methods using reagents like acetic anhydride and a catalyst such as pyridine, or through green chemistry approaches which are more environmentally friendly.
Conventional Method:

Selection of Reagent and Catalyst:

Acetic anhydride is commonly used as the acetylating agent.
Pyridine acts as a catalyst and base to absorb the hydrogen chloride produced in the reaction.


Procedure:

Dissolve the phenolic compound (e.g., β-naphthol, vanillin, or salicylic acid) in pyridine.
Add excess acetic anhydride to the solution.
Heat the mixture to promote the reaction.
Once the reaction is complete, pour the mixture into ice-cold water to precipitate the acetylated product.
Filter and wash the precipitate with water to obtain the pure acetylated product.



Green Chemistry Approach:

Principles Involved:

Utilize less hazardous chemicals and conditions.
Avoid the use of pyridine.


Procedure:

One green approach is to perform the acetylation in the presence of a catalytic amount of an ionic liquid instead of pyridine.
The reaction can be done at room temperature, dramatically reducing the need for heating.
After acetylation, the ionic liquid can be reused, reducing waste.


Outcome:

Green approaches minimize the environmental impact and improve the safety profile of the reaction.



Both methods yield an acetylated compound, which manifests as a product with altered physical properties, making it useful in various pharmaceutical and industrial applications. Understanding the methodology and principles of different acetylation approaches is crucial in synthetic organic chemistry.

Answered by SophiaElizab | 2025-07-07

Acetylation of salicylic acid can be done using a conventional method with acetic anhydride and pyridine or through a green chemistry approach using ionic liquids. The green method is more environmentally friendly and can often be performed at room temperature, reducing energy consumption. Both methods yield acetylsalicylic acid, useful in pharmaceuticals.
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Answered by SophiaElizab | 2025-07-07