What happens when salicylic acid reacts with acetic anhydride followed by acid hydrolysis?

What happens when salicylic acid reacts with acetic anhydride followed by acid hydrolysis?

The reaction for synthesis of acetylsalicylic acid is shown in the following figure. Salicylic acid, prepared from the hydrolysis of methylsalicylate is reacted with acetic anhydride producing the ester product, acetylsalicylic acid.

What happens when salicylic acid reacts with acetic acid?

It is then absorbed into the bloodstream. Aspirin can be made by reacting salicylic acid with acetic acid in the presence of an acid catalyst. The phenol group on the salicylic acid forms an ester with the carboxyl group on the acetic acid. However, this reaction is slow and has a relatively low yield.

Is the reaction between salicylic acid and acetic anhydride reversible?

This reaction is highly reversible, because carboxylic acids are approximately as reactive as esters. In order to obtain good yields of the ester, an excess of acetic acid can be used, which by Le Chatelier’s principle (see your General Chemistry textbook for a review) shifts the equilibrium toward the ester product.

Why do we use acetic anhydride instead of acetic acid?

Acetyl chloride and acetic anhydride are often used instead of acetic acid because they are more reactive and give better yields of product.

What happens to salicylic acid when heated?

Salicylic acid crystallizes in small colourless needles which melt at 1 55° C. It is sparingly soluble in cold water, but readily dissolves in hot. It sublimes, but on rapid heating decomposes into carbon dioxide and phenol. It is volatile in steam.

What is vinegar and how does it influence the chemical reactions taking place?

Vinegar is a solution of acetic acid in water. Acetic acid reacts with sodium bicarbonate to produce carbon dioxide, just as the citric acid in an effervescent tablet does.

Why does salicylic acid and acetic anhydride from aspirin?

To prepare aspirin, salicylic acid is reacted with an excess of acetic anhydride. A small amount of a strong acid is used as a catalyst which speeds up the reaction. Since acetic acid is very soluble in water, it is easily separated from the aspirin product. The aspirin isolated in this step is the “crude product”.

What is the chemical reaction involved in the synthesis of salicylic acid?

The reaction that is used for the synthesis is shown below. In this reaction, an excess of acetic anhydride (C4H6O3) is added to a measured mass of salicylic acid (C7H6O3) in the presence of a catalyst, sulfuric acid (H2SO4). The mixture is heated to form the acetylsalicylic acid (C9H8O4) and acetic acid (C2H4O2).

What is the mechanism of the acetylation reaction of salicylic acid?

The mechanism of the acetylation reaction undergone by salicylic acid to afford aspirin and acetic acid as the product is illustrated below. First, one oxygen atom of the acetic anhydride is protonated by the acid. The resulting positive charge is relayed to the adjacent carbonyl carbon, which binds itself to the phenolic hydroxy group.

How is aspirin synthesized from salicylic acid?

Synthesis of aspirin from salicylic acid occurs by acetylation process in acidic medium. Salicylic acid interacts with acetic anhydride in presence of few drops of concentrated sulphuric acid to produce aspirin and a molecule of acetic acid.

What is the purpose of adding sulphuric acid to salicylic acid?

The purpose of adding sulphuric acid (catalyst) is to aid and augent the process of detaching the acetate ion (CH3COO–) from acetic anhydride which ultimately gets associated with H+ ion from phenolic hydroxy group in salicylic acid to be eliminated as a mole of acetic acid.1 Aim: To prepare aspirin from salicylic acid.

How do you make acetic anhydride and sulphuric acid?

Add 8.5 ml acetic anhydride and 3-4 drops of concentrated sulphuric acid to the flask carefully and mix thoroughly. Warm the mixture on water bath at 60 degrees about 20 min with frequent stirring. Allow the contents in the flask to cool and pour into 100 ml cold water in 250 ml beaker with constant Stirring.