How is Acetanilide prepared from aniline?

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Acetanilide is prepared from aniline when it reacts with acetic anhydride/glacial acetic acid in the presence of zinc dust. A mixture of aniline, glacial acetic acid, acetic anhydride and zinc dust is refluxed under anhydrous condition and then poured the mixture into ice cold water to get acetic anhydride precipitate.

Why is Acetanilide nitrated and not aniline? Acetanilide is used instead of aniline for the nitration because aniline has an unwanted side reaction. The product of the third reaction is a diazonium salt, which is not isolated but is used immediately.

why use zinc dust in preparation of Acetanilide from aniline?

In the laboratory, acetylation of aniline is usually carried out with acetic anhydride in the presence of glacial acetic acid and zinc dust. The zinc dust helps to prevent the oxidation of aniline during the reaction. It also reduces the coloured impurities present in the solution.

Why is glacial acetic acid used in this reaction? See: What is glacial acetic acid? It can be used as a solvent or reagent for many reactions where water is preferably absent. It is miscible with other organic solvents. As a solvent it is useful in organic chemistry for purifying material by recrystallization.

why glacial acetic acid is used in preparation of Acetanilide from aniline?

Glacial acetic acid is used because it is an excellent polar protic solvent capable of dissolving acetanilide. For the process, acetanilide is first dissolved in the solvent, glacial acetic acid, by warming.

Is glacial acetic acid a catalyst?

Glacial acetic acid as a protic acid was employed as a catalyst in a solvent free condition for facile preparation of di(indolyl)methanes (DIMs) via one-pot condensation of indole with aryl or heteroaryl aldehydes.

why is freshly distilled aniline always preferred in the synthesis of Acetanilide?

Freshly distilled aniline should be used in order to get good results or small amount of zinc can be added in the reaction mixture. Zinc reduces the coloured impurities in the aniline and also prevents its oxidation during the reaction. 2. Prolonged heating and use of excess of acetic anhydride should be avoided.

What solvent will the Acetanilide be recrystallized from?

Acetanilide is readily soluble in ethanol at room temperature. So we can not use the ethanol as a solvent for acetanilide recrystallization. But it can soluble in water when heating. Therefore, water is the beat solvent for acetanilide.

What is the purpose of acetanilide in the preparation?

Acetanilide is used as an inhibitor of hydrogen peroxide decomposition and is used to stabilize cellulose ester varnishes. It has also found uses in the intermediation in rubber accelerator synthesis, dyes and dye intermediate synthesis, and camphor synthesis.

What is the role of acetic acid and pyridine in acetylation?

Acetic anhydride can be used with a basic catalyst, such as pyridine. This combination promotes smooth reactions and has great solvent power. Pyridine acts as an acceptor for the acid by-product formed in the reaction.

How will you prepare aniline in laboratory?

Aniline is prepared in the laboratory by reducing nitrobenzene with tin and concentrated hydrochloric acid. The acid salt of aniline is then treated with sodium hydroxide solution to liberate aniline. Aniline is separated from the mixture by steam distillation.

Where does acetic anhydride come from?

As the name indicates, an acid anhydride is a compound that is related to an acid by the loss of water. Acetic anhydride can by prepared by the dehydration of acetic acid at 800°C. Alternatively, the reaction between the acid chloride and a salt of acetic acid (e.g. sodium acetate) yields acetic anhydride and a salt.

How do you find theoretical yield of Acetanilide?

Theoretical yield is the molar mass the stoichiometry problem makes. Therefore, Your theoretical yield is 1 mol. Actual/Theoretical x 100 ===> 0.0048 mol/1mol = 0.0048 x 100 = 0.48% yield.

How do you recrystallize Acetanilide?

via recrystallization. Add ~5 drops of water to the tube and heat until the solid dissolves. Then let it cool on its own for 5 minutes before you put it an ice bath. Crystals should form.

What should be done if Acetanilide is Coloured?

If the solution is coloured, add a small amount of decolourising charcoal, swirl the flask for about one minute, and filter off the carbon using a fluted filter paper (see the Appendix). In a separate container dissolve 3 g sodium acetate in 10 mL water.

What is acetic acid in?

Acetic acid is one of the simplest carboxylic acids. It is an important chemical reagent and industrial chemical that is used in the production of plastic soft drink bottles, photographic film; and polyvinyl acetate for wood glue, as well as many synthetic fibres and fabrics.