P-bromoaniline can be synthesized from p-bromoacetanilide through a chemical reaction known as hydrolysis. Hydrolysis is a chemical reaction in which a compound is broken down into its constituent parts by the addition of water. In this case, the p-bromoacetanilide molecule is hydrolyzed to produce p-bromoaniline and acetic acid.
The mechanism of this reaction involves the attack of a water molecule on the acetyl group of the p-bromoacetanilide molecule. This results in the formation of a intermediate compound known as an acetylide ion, which is highly reactive and prone to further chemical reactions.
Next, the acetylide ion undergoes a nucleophilic substitution reaction with the bromine atom of the p-bromoacetanilide molecule. In this reaction, the acetylide ion acts as a nucleophile, which is a molecule with a lone pair of electrons that can be donated to form a covalent bond. The bromine atom, being an electrophile, accepts the electrons from the acetylide ion and forms a covalent bond, resulting in the formation of p-bromoaniline.
The overall reaction can be represented by the following equation:
p-bromoacetanilide + H2O → p-bromoaniline + acetic acid
In order to carry out this reaction, p-bromoacetanilide is dissolved in an aqueous solution and heated to a high temperature. An acid such as hydrochloric acid or sulfuric acid is typically added to the solution to provide the necessary proton needed for the hydrolysis reaction to occur. The resulting p-bromoaniline can be isolated and purified through a series of separation techniques, such as distillation or crystallization.
In summary, the mechanism of the synthesis of p-bromoaniline from p-bromoacetanilide involves the hydrolysis of the acetyl group followed by a nucleophilic substitution reaction with the bromine atom. This reaction requires the use of an aqueous solution and an acid catalyst, and the resulting p-bromoaniline can be purified through various separation techniques.