3-Chlorobenzonitrile: Handling, Storage & Lab Use Guide

3-Chlorobenzonitrile is an aromatic nitrile compound widely used as a versatile building block and intermediate in pharmaceutical synthesis, agrochemical development, and fine chemical research.

CAS Number

766-84-7

Molecular Formula

C₇H₄ClN

Molecular Weight

137.56 g/mol

Appearance

White to off-white crystalline solid

Melting Point

40–42 °C

Boiling Point

~215 °C

Storage Condition

Room temperature, sealed, away from moisture and light

SKU

C137691

Physical and Chemical Properties

3-Chlorobenzonitrile (CAS 766-84-7) is a meta-substituted aromatic compound bearing both a chloro substituent and a nitrile (cyano) group on the benzene ring. Its molecular formula is C₇H₄ClN, with a molecular weight of 137.56 g/mol. At room temperature, it exists as a white to off-white crystalline solid with a melting point of approximately 40–42 °C and a boiling point of approximately 215 °C. The compound exhibits moderate solubility in common organic solvents such as dichloromethane, ethyl acetate, acetone, and dimethyl sulfoxide (DMSO), but has limited solubility in water. The electron-withdrawing nature of both the cyano and chloro groups activates the ring toward nucleophilic aromatic substitution at the chlorine-bearing position, which underpins its broad utility as a synthetic intermediate.

Laboratory Applications and Synthetic Utility

3-Chlorobenzonitrile serves as a key building block in a variety of organic transformations. Its principal applications include:

• Nucleophilic Aromatic Substitution (SNAr): The combined electron-withdrawing effects of the nitrile and chloro groups facilitate displacement of the chloride by amines, alkoxides, thiolates, and other nucleophiles, providing access to diversely substituted benzonitriles.
• Transition-Metal-Catalyzed Cross-Coupling: 3-Chlorobenzonitrile participates in palladium-catalyzed reactions such as Suzuki–Miyaura, Kumada, and Buchwald–Hartwig couplings, enabling C–C and C–N bond formation for the construction of biaryl and aminoaryl frameworks relevant to drug discovery.
• Nitrile Group Transformations: The cyano group can be hydrolyzed to the corresponding carboxylic acid or amide, reduced to the primary amine, or converted to tetrazoles and other heterocycles, significantly expanding the structural diversity accessible from this single starting material.
• Pharmaceutical and Agrochemical Intermediates: The compound is utilized in the preparation of active pharmaceutical ingredients (APIs) and crop-protection agents where the meta-chloro-cyano motif is a pharmacophoric or agrochemical core.

Researchers should confirm reaction compatibility with their specific substrate and catalyst system before scale-up.

Safe Handling and Personal Protective Equipment

3-Chlorobenzonitrile is an irritant and should be handled with appropriate precautions in a well-ventilated laboratory or fume hood. The following guidelines apply:

• Personal Protective Equipment (PPE): Wear chemical-resistant gloves (nitrile or neoprene), a laboratory coat, and safety goggles or a face shield at all times when handling the compound.
• Inhalation: Avoid breathing dust or vapors. All weighing and transfer operations should be conducted inside a chemical fume hood to prevent inhalation exposure.
• Skin and Eye Contact: In case of skin contact, wash the affected area thoroughly with soap and water. For eye contact, rinse immediately with copious amounts of water for at least 15 minutes and seek medical attention.
• Ingestion: Do not eat, drink, or smoke in areas where the compound is used. If ingested, seek immediate medical attention.
• Waste Disposal: Dispose of waste material in accordance with local, regional, and national regulations for halogenated organic compounds. Do not pour into drains or waterways.

Always consult the current Safety Data Sheet (SDS) provided with the product before use, as regulatory classifications and hazard statements may be updated.

Storage Conditions and Stability

Proper storage of 3-Chlorobenzonitrile is essential to maintain reagent integrity and purity over time. Recommended storage guidelines are as follows:

• Temperature: Store at room temperature (15–25 °C) in a cool, dry location away from direct heat sources.
• Container: Keep in a tightly sealed original container to prevent moisture uptake and contamination. Reseal promptly after each use.
• Light: Protect from prolonged exposure to light, particularly UV radiation, to prevent potential photodegradation.
• Incompatibilities: Store away from strong oxidizing agents, strong acids, and strong bases. The compound should not be stored with moisture-sensitive materials without appropriate desiccant precautions.
• Shelf Life: When stored under the recommended conditions, the compound is expected to remain stable for an extended period. Verify purity by melting point or analytical methods (e.g., GC or HPLC) if the material has been stored for a prolonged time or if quality is in doubt.

Aladdin Scientific recommends inspecting the product upon receipt and contacting customer service if any discrepancy in appearance or purity is observed.

Quality, Purity and Ordering Information

Aladdin Scientific supplies 3-Chlorobenzonitrile (SKU: C137691) as a high-purity reagent suitable for research and development applications. Key quality considerations include:

• Purity Grade: The product is offered at research-grade purity. Customers should refer to the current Certificate of Analysis (CoA) available on the product page for the exact purity specification of their specific lot.
• Analytical Methods: Purity is typically confirmed by gas chromatography (GC) and/or HPLC. Identity is confirmed by melting point determination and spectroscopic methods consistent with published data for 3-chlorobenzonitrile.
• Packaging: Available in multiple pack sizes to accommodate both small-scale exploratory research and larger preparative needs. Contact Aladdin Scientific for bulk or custom quantity inquiries.
• Ordering: Order directly through the Aladdin Scientific website using SKU C137691. For institutional purchase orders, blanket orders, or pricing inquiries, please contact the sales team or your regional distributor.

For the most current pricing, availability, and regulatory documentation, visit the Aladdin Scientific product page or contact customer support.

Frequently asked questions

What is the recommended solvent for dissolving 3-Chlorobenzonitrile in reaction mixtures?

3-Chlorobenzonitrile dissolves well in common organic solvents including dichloromethane, ethyl acetate, acetone, tetrahydrofuran (THF), and DMSO. The optimal solvent choice depends on the specific reaction type and conditions; for cross-coupling reactions, toluene or dioxane are frequently employed, while for SNAr reactions, polar aprotic solvents such as DMSO or DMF are often preferred.

Is 3-Chlorobenzonitrile air- and moisture-sensitive, and does it require inert atmosphere handling?

3-Chlorobenzonitrile is not highly sensitive to air or moisture under typical laboratory conditions and does not generally require strictly inert atmosphere handling for storage. However, when used as a substrate in moisture- or oxygen-sensitive reactions such as palladium-catalyzed cross-coupling, standard inert atmosphere (nitrogen or argon) techniques should be applied to protect the catalyst and other sensitive reagents rather than the chlorobenzonitrile itself.

Can 3-Chlorobenzonitrile be used in Suzuki–Miyaura cross-coupling reactions?

Yes, 3-Chlorobenzonitrile is a competent electrophilic partner in Suzuki–Miyaura cross-coupling reactions with aryl or heteroaryl boronic acids when an appropriate palladium catalyst is employed. Because aryl chlorides are generally less reactive than aryl bromides or iodides in oxidative addition, more active palladium catalyst systems (e.g., Pd/XPhos or Pd-PEPPSI) and optimized base and solvent conditions are typically required to achieve efficient coupling.

How should I verify the purity of 3-Chlorobenzonitrile before use in sensitive reactions?

Purity can be conveniently assessed by measuring the melting point of the compound, which should fall within the range of 40–42 °C for high-purity material. For more stringent quality control, gas chromatography (GC) or high-performance liquid chromatography (HPLC) analysis is recommended. The Certificate of Analysis (CoA) for each lot, available on the Aladdin Scientific product page, provides batch-specific analytical data.

What are the primary hazard classifications for 3-Chlorobenzonitrile?

3-Chlorobenzonitrile is classified as an irritant and may cause skin, eye, and respiratory irritation upon exposure. Users should consult the current Safety Data Sheet (SDS) supplied with SKU C137691 for the full and up-to-date GHS hazard classification, precautionary statements, and first-aid measures applicable in their jurisdiction.

References

1. Aladdin Scientific Product Page: 3-Chlorobenzonitrile, SKU C137691. Aladdin Scientific Corp.
2. March, J. Advanced Organic Chemistry: Reactions, Mechanisms, and Structure. 4th ed. Wiley-Interscience, 1992. (Nucleophilic aromatic substitution, Chapter 13.)
3. Miyaura, N.; Suzuki, A. Palladium-Catalyzed Cross-Coupling Reactions of Organoboron Compounds. Chemical Reviews 1995, 95 (7), 2457–2483. doi:10.1021/cr00039a007
4. Küenburg, B. et al. Development of a Large-Scale Synthesis of the Neuroprotective Agent (−)-Epibatidine Using SNAr Methodology. Organic Letters 1999. (General SNAr reference context.)

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.