Final answer:
Paracetamol (acetaminophen) can be synthesized from p-aminophenol or phenol. The synthesis from p-aminophenol involves protecting the amino group, oxidizing, reducing, acetylating, and then hydrolysing. The synthesis from phenol involves protecting the hydroxyl group, brominating, aminating, acetylating, and then hydrolysing.
Step-by-step explanation:
Paracetamol, also known as acetaminophen, can be synthesized through a retrosynthetic analysis and subsequent synthesis. The retrosynthetic analysis involves breaking down the target molecule into smaller fragments and identifying possible synthetic routes. In the case of paracetamol, it can be synthesized from p-aminophenol or phenol.
- The synthesis from p-aminophenol involves the following steps:
- Protecting the amino group with an acetyl group using acetic anhydride and pyridine.
- Oxidation of the protected amine using sodium dichromate and glacial acetic acid to form p-nitrobenzene.
- Reduction of the nitro group to an amine using iron and hydrochloric acid.
- Acetylation of the amine using acetic anhydride to form p-acetaminobenzene.
- Formation of paracetamol by hydrolysis of the acetyl group using hydrochloric acid and heating.
The synthesis from phenol involves the following steps:
- Protecting the hydroxyl group with an acetyl group using acetic anhydride and pyridine.
- Conversion of the protected hydroxyl group to a bromine atom using phosphorus tribromide.
- Replacement of the bromine atom with an amino group using ammonia and copper(I) oxide.
- Acetylation of the amino group using acetic anhydride to form N-acetyl-p-aminophenol.
- Formation of paracetamol by hydrolysis of the acetyl group using hydrochloric acid and heating.
Learn more about synthesis and retrosynthesis of paracetamol