4-Chloro-7-Hydroxyquinoline: Properties, Uses & FAQs

4-Chloro-7-hydroxyquinoline is a halogenated quinoline derivative bearing both a chloro substituent at the 4-position and a hydroxyl group at the 7-position, making it a versatile bifunctional building block widely used in medicinal chemistry and organic synthesis.

CAS Number

Not confirmed in source material — see review flag

Molecular Formula

C9H6ClNO

Molecular Weight

179.60 g/mol

Key Functional Groups

Chloro (C-4), Hydroxyl (C-7), Quinoline ring system

Primary Applications

Pharmaceutical intermediate, heterocyclic synthesis, medicinal chemistry research

SKU

C1369509

What Is 4-Chloro-7-Hydroxyquinoline?

4-Chloro-7-hydroxyquinoline is a substituted quinoline compound in which a chlorine atom occupies the 4-position and a hydroxyl group occupies the 7-position of the bicyclic aromatic quinoline scaffold. The quinoline ring system consists of a benzene ring fused to a pyridine ring, conferring aromatic stability and a planar structure favorable for intercalation and binding interactions in biological systems.

The combination of an electrophilic chloro group and a nucleophilic hydroxyl group on the same scaffold makes this compound particularly valuable as a synthetic intermediate. The C-4 chloro group is susceptible to nucleophilic aromatic substitution (SNAr), allowing straightforward introduction of amines, thiols, and other nucleophiles, while the C-7 hydroxyl can be functionalized via O-alkylation, O-acylation, or converted to other leaving groups.

Physicochemical Properties and Solubility

4-Chloro-7-hydroxyquinoline is typically a solid at room temperature with a molecular weight of approximately 179.60 g/mol and the molecular formula C9H6ClNO. Its aromatic, planar structure contributes to relatively high melting points characteristic of quinoline derivatives.

Solubility: As a moderately polar heterocyclic compound, 4-Chloro-7-hydroxyquinoline shows limited solubility in water but is generally soluble in polar aprotic solvents such as dimethyl sulfoxide (DMSO) and dimethylformamide (DMF), as well as in alcohols such as methanol and ethanol. For biological assay preparations, stock solutions are commonly prepared in DMSO and diluted into aqueous buffer. Researchers should verify actual solubility under their specific experimental conditions.

Note: Exact melting point, logP, and pKa values are not confirmed in the current source material and have been flagged for review.

Storage, Handling, and Safety Considerations

Storage: 4-Chloro-7-hydroxyquinoline should be stored in a tightly sealed container away from light, heat, and moisture. Storage at room temperature (15–25 °C) under dry conditions is generally appropriate for stable solid heterocyclic intermediates; however, researchers should consult the product-specific Safety Data Sheet (SDS) provided by Aladdin Scientific for confirmed storage temperature recommendations.

Handling: As with all fine chemical reagents, appropriate personal protective equipment (PPE) should be used, including laboratory coat, nitrile gloves, and safety glasses. Work should be conducted in a well-ventilated area or fume hood. Avoid inhalation of dust and contact with skin or eyes.

Disposal: Dispose of waste material in accordance with local, regional, and national regulations applicable to halogenated organic compounds. Consult your institution's environmental health and safety (EHS) office for guidance.

Specific hazard classifications (GHS pictograms, H-statements, P-statements) are not confirmed in the current source material; please refer to the official Aladdin SDS for product C1369509.

Applications in Research and Synthesis

Pharmaceutical Intermediate: 4-Chloro-7-hydroxyquinoline serves as a key building block in the synthesis of biologically active quinoline derivatives. Quinoline-based compounds constitute an important class of pharmacophores with reported activities spanning antimalarial, antibacterial, antifungal, antiviral, and anticancer domains. The dual reactivity of this compound enables library synthesis for drug discovery programs.

Nucleophilic Aromatic Substitution (SNAr): The electron-deficient quinoline ring activated by the ring nitrogen renders the C-4 chloro group highly reactive toward SNAr reactions with primary and secondary amines, alkoxides, and thiolates. This makes the compound ideal for generating 4-amino-, 4-alkoxy-, or 4-thio-7-hydroxyquinoline analogs.

O-Functionalization: The C-7 hydroxyl group can be selectively alkylated or acylated to yield ethers and esters, providing orthogonal synthetic handles for building structurally diverse quinoline libraries.

Coordination Chemistry: Hydroxyquinoline motifs are well known as chelating ligands for metal ions. The 7-hydroxy group, in conjunction with the quinoline nitrogen, can coordinate to transition metals, suggesting potential applications in the development of metal-responsive probes or catalysts.

Ordering and Quality Information

4-Chloro-7-hydroxyquinoline is available from Aladdin Scientific under SKU C1369509. To place an order or request a quotation, visit the Aladdin Scientific website or contact your regional sales representative.

Purity and Quality: Aladdin Scientific provides reagents with defined purity specifications. Customers requiring certificate of analysis (CoA), nuclear magnetic resonance (NMR) spectra, or high-performance liquid chromatography (HPLC) purity data for lot-specific quality assurance should request these documents at the time of ordering or through the customer service portal.

Custom Quantities: If your research requires quantities not listed in the standard catalog, please contact Aladdin Scientific's customer service team to discuss custom packaging or bulk supply options.

Returns and Exchanges: Please refer to Aladdin Scientific's Returns and Refunds policy for information on eligibility and procedures. Chemical products are subject to specific return conditions due to regulatory and safety requirements.

Frequently asked questions

What is the molecular formula and molecular weight of 4-Chloro-7-hydroxyquinoline?

4-Chloro-7-hydroxyquinoline has the molecular formula C9H6ClNO and a molecular weight of approximately 179.60 g/mol. It contains a quinoline bicyclic aromatic core substituted with a chlorine at C-4 and a hydroxyl group at C-7.

In which solvents is 4-Chloro-7-hydroxyquinoline soluble?

4-Chloro-7-hydroxyquinoline has limited water solubility due to its aromatic heterocyclic character. It is generally soluble in polar aprotic solvents such as DMSO and DMF, and in protic solvents such as methanol and ethanol. For biological assays, a DMSO stock solution diluted into aqueous buffer is a common approach; researchers should experimentally verify solubility under their specific conditions.

What are the main synthetic applications of 4-Chloro-7-hydroxyquinoline?

The compound serves as a bifunctional intermediate in medicinal chemistry. The C-4 chloro group undergoes nucleophilic aromatic substitution (SNAr) with amines, thiols, and alkoxides to provide 4-substituted quinoline analogs, while the C-7 hydroxyl can be independently alkylated or acylated. This orthogonal reactivity makes it ideal for building diverse quinoline-based compound libraries for drug discovery.

How should 4-Chloro-7-hydroxyquinoline be stored?

The compound should be stored in a tightly sealed container, protected from light and moisture, at controlled room temperature. Always consult the product-specific Safety Data Sheet (SDS) for SKU C1369509 available from Aladdin Scientific for confirmed storage conditions and hazard information.

How can I order 4-Chloro-7-hydroxyquinoline from Aladdin Scientific?

4-Chloro-7-hydroxyquinoline is listed in the Aladdin Scientific catalog under SKU C1369509. You can place an order directly through the Aladdin Scientific website, contact your regional sales representative, or reach out to customer service for bulk quantities, custom packaging, or to request a certificate of analysis.

What safety precautions should be taken when handling 4-Chloro-7-hydroxyquinoline?

Standard laboratory safety precautions apply: wear a lab coat, nitrile gloves, and safety glasses, and handle the compound in a well-ventilated area or fume hood to avoid inhalation of dust. Specific GHS hazard classifications have not been confirmed in available source material; refer to the official Aladdin Scientific SDS for product C1369509 for authoritative hazard and first-aid information.

References

1. Aladdin Scientific Product Catalog: 4-Chloro-7-hydroxyquinoline, SKU C1369509.
2. March, J. Advanced Organic Chemistry: Reactions, Mechanisms, and Structure. Wiley-Interscience. General reference for nucleophilic aromatic substitution reactions of halogenated heterocycles.
3. Manske, R.H.F. (Ed.) The Chemistry of Heterocyclic Compounds: Quinolines. General textbook reference for quinoline chemistry and reactivity.

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