4-Aminophenol

4-Aminophenol is an organic compound that belongs to the class of aniline derivatives. It is composed of a phenol molecule in which one of the hydrogen atoms is replaced by an amino group. The chemical formula of 4-aminophenol is C₆H₇NO, and it is also known by other names such as p-aminophenol, para-aminophenol, and 4-hydroxyaniline.

Structure and Properties

4-Aminophenol consists of a benzene ring that is substituted with an amino group (-NH₂) at the para position and a hydroxyl group (-OH) at the opposite position. This structural arrangement contributes to its chemical and physical properties. The compound appears as a white crystalline powder that is slightly soluble in water and more soluble in organic solvents such as ethanol and ether.

The presence of both the amino and hydroxyl groups in 4-aminophenol allows it to participate in various chemical reactions, making it a valuable intermediate in the synthesis of dyes, drugs, and other chemicals. Its melting point is around 187°C, and it has a molecular weight of 109.13 g/mol.

Synthesis

4-Aminophenol can be synthesized through several methods. One common approach involves the reduction of nitrobenzene to phenylhydroxylamine, which is then rearranged in the presence of an acid to yield 4-aminophenol. Another method is the hydrolysis of 4-nitrophenol.

Applications

The primary use of 4-aminophenol is in the pharmaceutical industry, where it serves as a precursor in the synthesis of paracetamol (acetaminophen), a widely used analgesic and antipyretic drug. Additionally, it is employed in the manufacture of various dyes, photographic developers, and antioxidants for rubber.

Safety and Toxicology

Exposure to 4-aminophenol can pose health risks, including skin irritation, respiratory issues, and potential toxicity if ingested. It is considered a hazardous substance, and appropriate safety measures should be taken when handling it. The compound can also have environmental impacts if not properly managed.

Environmental Impact

Proper disposal and treatment of 4-aminophenol waste are crucial to prevent environmental contamination. Its presence in water bodies can be harmful to aquatic life due to its toxicity.

See Also

• Phenol
• Aniline
• Paracetamol
• Nitrobenzene