Understanding 4-Bromo-2-nitroanisole: Properties, Characterization & Safety
In the realm of fine chemicals and organic synthesis, a thorough understanding of a compound's properties, analytical characterization, and safety protocols is crucial for effective utilization. 4-Bromo-2-nitroanisole (CAS: 33696-00-3) is a widely used intermediate, and grasping its characteristics is key for researchers, chemists, and procurement specialists. As a responsible supplier, we provide comprehensive insights into this compound.
Key Physical and Chemical Properties
4-Bromo-2-nitroanisole is typically described as a light yellow crystalline powder. Its key properties include:
- Molecular Formula: C₇H₆BrNO₃
- Molecular Weight: Approximately 232.03 g/mol
- Melting Point: Typically reported in the range of 81-87 °C (though some sources indicate up to 100 °C, indicating potential purity variations). A sharp melting point range generally signifies high purity.
- Appearance: Light yellow crystalline powder.
- Solubility: Insoluble in water at room temperature, but soluble in many organic solvents, which is typical for compounds of this nature and facilitates its use in organic reactions.
- Density: Around 1.640 g/cm³.
- Boiling Point: Approximately 303.3 °C at 760 mmHg (predicted).
- Flash Point: Around 137.2 °C.
These properties provide fundamental information for handling, storage, and its suitability for various reaction conditions.
Characterization Techniques: Ensuring Identity and Purity
Verifying the identity and purity of 4-Bromo-2-nitroanisole is essential for its reliable use in synthesis. Common analytical techniques employed include:
- Nuclear Magnetic Resonance (NMR) Spectroscopy: Both ¹H NMR and ¹³C NMR are vital for confirming the molecular structure. The ¹H NMR spectrum will show characteristic signals for the aromatic protons and a singlet for the methoxy group protons. ¹³C NMR provides signals for each unique carbon atom, confirming the substitution pattern.
- Mass Spectrometry (MS): MS is used to determine the molecular weight and fragmentation pattern. The presence of a single bromine atom is confirmed by the characteristic isotopic pattern (M⁺ and M+2 peaks of nearly equal intensity). High-resolution MS can provide precise elemental composition.
- High-Performance Liquid Chromatography (HPLC): HPLC is the gold standard for assessing purity. Reverse-phase HPLC methods, often coupled with UV detection, can quantify the main compound and identify/quantify impurities, with purity typically specified as ≥98.0%.
- Infrared (IR) Spectroscopy: IR spectroscopy confirms the presence of key functional groups, notably the strong absorption bands for the nitro group (~1520 cm⁻¹ and ~1340 cm⁻¹) and characteristic bands for the methoxy and C-Br bonds.
- Melting Point Determination: As mentioned, a sharp melting point within the expected range is a strong indicator of purity.
These methods, when used in conjunction, provide irrefutable evidence of the compound's identity and purity.
Safety and Handling Considerations
Like many nitroaromatic compounds, 4-Bromo-2-nitroanisole requires careful handling. It is generally classified as an irritant.
- Hazard Symbols: Often displays an 'Xi' (Irritant) symbol.
- Handling: Avoid contact with skin, eyes, and clothing. Wear appropriate personal protective equipment (PPE), including gloves, eye protection, and protective clothing. Ensure adequate ventilation or use in a fume hood.
- Storage: Store in a cool, well-ventilated place, away from heat and ignition sources. Keep containers tightly closed to prevent moisture absorption and degradation. Recommended storage conditions often specify refrigeration (2-8 °C) to maintain stability and prevent photolytic decomposition.
- Disposal: Dispose of waste material in accordance with local, regional, and national regulations for chemical waste.
Understanding these properties and employing safe laboratory practices are paramount when working with 4-Bromo-2-nitroanisole. We are committed to providing not only high-quality chemical products but also the necessary information to ensure their safe and effective use. For detailed safety data sheets (SDS) and further technical inquiries, please contact us.
Perspectives & Insights
Future Origin 2025
“The ¹H NMR spectrum will show characteristic signals for the aromatic protons and a singlet for the methoxy group protons.”
Core Analyst 01
“¹³C NMR provides signals for each unique carbon atom, confirming the substitution pattern.”
Silicon Seeker One
“Mass Spectrometry (MS): MS is used to determine the molecular weight and fragmentation pattern.”