samir234
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Jan 10, 2025
1:25 AM
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2-Bromophenol
is an aromatic halogenated phenol compound commonly used as a building block in organic synthesis. It is an ortho-substituted bromophenol, where a bromine atom is attached to the benzene ring at the second position relative to the hydroxyl group (-OH). The presence of both hydroxyl and halogen groups makes it a versatile reagent in the synthesis of pharmaceuticals, agrochemicals, and fine chemicals.
Chemical Structure and Properties
Property Description
Chemical Name 2-Bromophenol
Molecular Formula C?H?BrO
Molecular Weight 173.01 g/mol
CAS Number 95-56-7
Appearance White to pale yellow crystalline solid
Boiling Point 210°C
Melting Point 7°C
Density 1.77 g/cm³
Solubility Slightly soluble in water, soluble in organic solvents like ethanol, ether, and chloroform
Chemical Structure
The structure of 2-bromophenol consists of a benzene ring with two functional groups:
Hydroxyl group (-OH) at the first position.
Bromine atom (Br) at the second position (ortho position).
This combination gives the molecule unique chemical and physical properties, including polarity, reactivity, and solubility.
Synthesis of 2-Bromophenol
2-Bromophenol can be synthesized by:
Bromination of Phenol:
Phenol undergoes electrophilic aromatic substitution with bromine in the presence of a catalyst (like FeBr?), resulting in bromophenol. By controlling the reaction conditions, the ortho isomer (2-bromophenol) can be selectively produced.
Reaction:
?
BrOH+HBr
Direct Bromination with NBS (N-Bromosuccinimide):
NBS is used as a brominating agent in the presence of a radical initiator (like light or peroxide) to selectively brominate phenol derivatives at the ortho position.
Applications of 2-Bromophenol
Intermediate in Pharmaceutical Synthesis:
2-Bromophenol is a key starting material in the production of antifungal agents, analgesics, and anti-inflammatory drugs.
It is used to prepare brominated benzodiazepines and other heterocyclic compounds.
Building Block in Organic Synthesis:
It is used as a precursor for the synthesis of aryl ethers, aryl amines, and aryl halides.
The hydroxyl and bromine groups facilitate substitution and coupling reactions, such as:
Suzuki coupling
Buchwald-Hartwig amination
Ullmann reaction
Agrochemical Synthesis:
Used in the preparation of fungicides, herbicides, and pesticides.
Polymer Chemistry:
It is employed in the modification of polymers and resins, improving their chemical and thermal properties.
Dye and Pigment Manufacturing:
The compound is used in the synthesis of azo dyes and organic pigments.
Biochemical Studies:
It serves as a model compound in studying the interaction of phenolic compounds with biological systems, particularly their role in enzyme inhibition and antioxidant activity.
Reactivity of 2-Bromophenol
2-Bromophenol exhibits both nucleophilic and electrophilic reactivity due to the presence of the hydroxyl and bromine groups:
Nucleophilic Substitution (SNAr):
The bromine atom can be displaced by a nucleophile (e.g., amine, thiol, or alkoxide) to form various derivatives.
Electrophilic Substitution:
The hydroxyl group activates the benzene ring, making it more susceptible to further electrophilic substitutions, such as nitration, sulfonation, or alkylation.
Oxidation:
The hydroxyl group can be oxidized to form quinones or other oxidized phenol derivatives.
Safety and Handling
2-Bromophenol is classified as a hazardous substance and should be handled with care.
Hazards:
Causes skin and eye irritation.
Harmful if inhaled or ingested.
Can cause environmental damage if released into water bodies.
Precautions:
Wear PPE: Gloves, goggles, and a lab coat should be worn while handling.
Work in a fume hood: Avoid inhaling vapors.
Proper storage: Keep in a cool, dry place, away from heat, moisture, and incompatible substances (e.g., strong oxidizers).
First Aid Measures:
Skin contact: Wash thoroughly with soap and water.
Eye contact: Rinse with water for at least 15 minutes and seek medical attention.
Inhalation: Move to fresh air immediately and seek medical help if symptoms persist.
Environmental Impact
2-Bromophenol can be toxic to aquatic life and should not be released into the environment. Proper waste disposal methods must be followed in compliance with local regulations.
Conclusion
2-Bromophenol is a valuable reagent in organic synthesis, particularly in the pharmaceutical and agrochemical industries. Its unique structure and reactivity make it an important intermediate in various chemical transformations. While it is a useful compound, appropriate safety precautions should be taken to handle it safely due to its hazardous properties.
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