2-Bromo-6-nitrophenol: Properties, Synthesis & Lab Uses

2-Bromo-6-nitrophenol is a halogenated aromatic compound widely employed as a versatile intermediate in organic synthesis, pharmaceutical research, and agrochemical development.

IUPAC Name

2-bromo-6-nitrophenol

CAS Number

13073-27-3

Molecular Formula

C₆H₄BrNO₃

Molecular Weight

218.00 g/mol

Appearance

Yellow to pale-brown crystalline solid

Key Functional Groups

Phenol (–OH), bromine substituent, nitro group (–NO₂)

SKU (Aladdin)

B152692

Chemical Identity and Physical Properties

2-Bromo-6-nitrophenol (CAS 13073-27-3) is an ortho-disubstituted phenol bearing a bromine atom at the 2-position and a nitro group at the 6-position relative to the hydroxyl group. Its molecular formula is C₆H₄BrNO₃ with a molecular weight of approximately 218.00 g/mol.

The compound typically presents as a yellow to pale-brown crystalline solid at room temperature. The simultaneous presence of a strong electron-withdrawing nitro group and a moderately electron-withdrawing bromine atom on the phenol ring significantly reduces the electron density of the aromatic system, affecting both reactivity and acidity. The intramolecular proximity of the hydroxyl and nitro groups can permit weak intramolecular hydrogen bonding, influencing the compound's melting point and solubility profile.

2-Bromo-6-nitrophenol is generally soluble in common polar organic solvents such as ethanol, acetone, dimethyl sulfoxide (DMSO), and ethyl acetate, but exhibits limited solubility in water. Researchers should store the material in a cool, dry, well-ventilated location away from strong oxidizers and bases.

Synthesis and Preparation Routes

2-Bromo-6-nitrophenol can be prepared via several established synthetic strategies commonly described in the organic chemistry literature. The two principal routes involve: (1) selective bromination of 2-nitrophenol, and (2) selective nitration of 2-bromophenol.

Route 1 – Bromination of 2-nitrophenol: Treatment of 2-nitrophenol with a suitable brominating agent (such as bromine in acetic acid or N-bromosuccinimide under controlled conditions) can introduce a bromine atom at the 6-position. Regioselectivity is influenced by the ortho/para-directing nature of the hydroxyl group and the meta-directing effect of the nitro group, which together favor electrophilic substitution at the position ortho to –OH and meta to –NO₂ (i.e., the 6-position).

Route 2 – Nitration of 2-bromophenol: Controlled mononitration of 2-bromophenol using dilute mixed acid (HNO₃/H₂SO₄) at low temperature can yield a mixture of nitrated isomers; reaction conditions must be carefully optimized to maximize formation of the 6-nitro isomer and minimize polynitration.

In both cases, purification is typically accomplished by recrystallization from suitable organic solvents or by column chromatography. Researchers are advised to validate purity by ¹H NMR, ¹³C NMR, and HPLC analysis prior to use in sensitive downstream applications.

Research Applications

2-Bromo-6-nitrophenol serves as a multifunctional building block in modern organic and medicinal chemistry. Its distinct combination of reactive functional groups — a phenolic hydroxyl, a C–Br bond amenable to cross-coupling, and a reducible nitro group — makes it especially valuable for the construction of complex molecules.

Cross-coupling chemistry: The aryl C–Br bond participates readily in transition-metal-catalyzed reactions, including Suzuki–Miyaura, Buchwald–Hartwig, and Ullmann-type couplings, enabling introduction of aryl, heteroaryl, or amino substituents at the 2-position while other functional groups remain intact.

Pharmaceutical and agrochemical intermediates: The nitro group can be selectively reduced to an amine (–NH₂) using catalytic hydrogenation or chemical reductants (e.g., Fe/AcOH, SnCl₂), providing an ortho-amino phenol derivative useful for constructing benzoxazole, benzimidazole, or other heterocyclic scaffolds found in drug candidates and crop-protection agents.

Dye and pigment synthesis: Halogenated nitrophenols have historical and contemporary utility in the synthesis of azo dyes and specialty colorants, where the electron-poor aromatic ring participates in coupling reactions or serves as a chromophore precursor.

Analytical and biochemical applications: Nitrophenol derivatives are employed as chromogenic substrates and reference standards in enzyme assay development; researchers should evaluate 2-Bromo-6-nitrophenol for suitability in specific assay contexts.

Safety, Handling, and Storage

2-Bromo-6-nitrophenol is an irritant and should be handled with appropriate personal protective equipment (PPE), including chemical-splash goggles, nitrile or neoprene gloves, and a laboratory coat. Work should be conducted in a well-ventilated fume hood to minimize inhalation of dust or vapors.

The compound should be kept away from strong oxidizing agents, strong bases, and reducing agents, as incompatible combinations may produce hazardous reactions. Nitro-aromatic compounds may present additional thermal sensitivity; avoid exposure to open flames or high temperatures.

Store in a tightly sealed container in a cool (typically 2–8 °C or as specified on the product label), dry location, protected from light. Keep out of drains and the environment. Disposal must comply with all applicable local, regional, and national regulations governing halogenated and nitro-aromatic waste streams.

Consult the Safety Data Sheet (SDS) provided by Aladdin Scientific (SKU B152692) for full hazard classifications, first-aid measures, and emergency response information before handling this compound.

Specifications and Quality Considerations

When selecting 2-Bromo-6-nitrophenol for research use, purity is a critical parameter. Aladdin Scientific offers this compound under SKU B152692; researchers should verify the purity specification (e.g., ≥97% or ≥98% by HPLC or GC) stated on the current Certificate of Analysis (CoA) prior to ordering, as specifications may be updated.

Key analytical data typically reported for this compound include: melting point range (to confirm identity and purity), ¹H NMR spectrum (to confirm substitution pattern and absence of isomeric impurities), and chromatographic purity (HPLC or GC). Researchers performing sensitive reactions — such as asymmetric catalysis or biological assays — should request the most recent CoA and, where necessary, perform in-house purity verification.

Packaging is available in multiple quantities to suit discovery-scale and scale-up needs. Contact Aladdin Scientific's technical or sales team for bulk quotations, custom packaging, or questions about analytical documentation.

Frequently asked questions

What is the CAS number for 2-Bromo-6-nitrophenol?

The CAS registry number for 2-Bromo-6-nitrophenol is 13073-27-3. This number uniquely identifies the compound and can be used to cross-reference safety data, literature, and supplier catalogues.

What solvents are suitable for dissolving 2-Bromo-6-nitrophenol?

2-Bromo-6-nitrophenol is generally soluble in polar organic solvents including ethanol, acetone, DMSO, and ethyl acetate. It has limited solubility in water. Always test solubility under your specific experimental conditions before use.

Can 2-Bromo-6-nitrophenol be used in palladium-catalyzed cross-coupling reactions?

Yes, the aryl C–Br bond in 2-Bromo-6-nitrophenol makes it a suitable electrophilic partner in palladium-catalyzed cross-coupling reactions such as Suzuki–Miyaura and Buchwald–Hartwig couplings. The phenolic hydroxyl group may need to be protected or the reaction conditions carefully optimized to avoid undesired side reactions.

How should 2-Bromo-6-nitrophenol be stored?

Store 2-Bromo-6-nitrophenol in a tightly sealed container in a cool, dry, dark location (typically 2–8 °C or as specified on the product label). Keep away from strong oxidizers, bases, and reducing agents. Always consult the current SDS for full storage guidance.

What PPE is recommended when handling 2-Bromo-6-nitrophenol?

Recommended PPE includes chemical-splash safety goggles, nitrile or neoprene gloves, and a laboratory coat. Work should be performed in a well-ventilated fume hood. Consult the Safety Data Sheet (SDS) for complete hazard and protective information.

References

1. March, J. Advanced Organic Chemistry: Reactions, Mechanisms, and Structure, 4th ed.; Wiley-Interscience: New York, 1992.
2. Clayden, J.; Greeves, N.; Warren, S. Organic Chemistry, 2nd ed.; Oxford University Press: Oxford, 2012.
3. Miyaura, N.; Suzuki, A. Palladium-Catalyzed Cross-Coupling Reactions of Organoboron Compounds. Chem. Rev. 1995, 95, 2457–2483. doi:10.1021/cr00039a007
4. Aladdin Scientific. 2-Bromo-6-nitrophenol, SKU B152692. Product page and Safety Data Sheet. Aladdin Scientific Corp.

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