6-Chloro-3-nitroquinolin-4-ol: Properties & Lab Handling Guide

6-Chloro-3-nitroquinolin-4-ol is a halogenated, nitro-substituted quinolinol building block widely employed in medicinal chemistry and heterocyclic synthesis as a versatile electrophilic intermediate.

IUPAC Name

6-Chloro-3-nitroquinolin-4-ol

CAS Number

Review required — not confirmed in source material

Molecular Formula

C₉H₅ClN₂O₃

Molecular Weight

224.60 g/mol (calculated)

Functional Groups

Chloro (C-6), nitro (C-3), hydroxyl/lactam (C-4) on quinoline scaffold

Aladdin SKU

C189346

Primary Use

Heterocyclic synthesis intermediate; medicinal chemistry building block

Chemical Structure and Key Properties

6-Chloro-3-nitroquinolin-4-ol belongs to the quinolinol (4-hydroxyquinoline) family of heterocyclic compounds. Its bicyclic aromatic scaffold carries three strategically positioned substituents: a chlorine atom at the 6-position, a nitro group at the 3-position, and a hydroxyl (or tautomeric keto/lactam) group at the 4-position.

The compound exists predominantly in the 4-quinolinone (lactam) tautomeric form in the solid state, a behaviour well-documented for 4-hydroxyquinolines. The electron-withdrawing nitro group at C-3 significantly increases the electrophilicity of the C-4 position and activates the ring toward nucleophilic aromatic substitution, while the C-6 chloro substituent provides an additional site for cross-coupling reactions (e.g., Suzuki, Buchwald–Hartwig) or further nucleophilic displacement.

Calculated physicochemical data (review recommended):

• Molecular formula: C₉H₅ClN₂O₃
• Molecular weight: 224.60 g/mol
• Appearance: Typically a pale yellow to off-white crystalline solid
• Solubility: Sparingly soluble in water; moderately soluble in polar aprotic solvents such as DMSO and DMF

Note: Exact physicochemical values (melting point, logP, pKa) were not available in the source material and should be verified against the certificate of analysis (CoA) supplied with SKU C189346.

Research Applications and Synthetic Utility

6-Chloro-3-nitroquinolin-4-ol is valued in synthetic and medicinal chemistry primarily as a multifunctional building block for the preparation of diversely substituted quinoline derivatives. The quinoline scaffold is a privileged structure in drug discovery, present in numerous approved pharmaceuticals with antibacterial, antimalarial, antiviral, and anticancer profiles.

Key synthetic applications include:

• Nucleophilic Aromatic Substitution (SNAr): The activated C-4 position (bearing the hydroxyl/lactam oxygen) and C-6 chloro group are susceptible to displacement by amines, thiols, and alkoxides, enabling rapid diversification of the quinoline core.
• Palladium-Catalysed Cross-Coupling: The C-6 aryl chloride can participate in Suzuki–Miyaura, Negishi, or Buchwald–Hartwig reactions to introduce aryl, alkyl, or amino groups.
• Nitro Group Reduction: Catalytic hydrogenation or chemical reduction (e.g., Fe/AcOH, SnCl₂) of the C-3 nitro group affords the corresponding 3-aminoquinolinone, a versatile intermediate for further functionalisation including heterocycle formation.
• Heterocycle Annulation: The proximal nitro and carbonyl (or hydroxyl) groups can be exploited to construct fused ring systems such as benzimidazoles, quinoxalines, or pyrazolo-quinolines.

Specific literature precedents citing this exact compound were not available in the source material; applications described are based on established reactivity of analogous nitroquinolinol scaffolds.

Safe Handling, Storage, and Waste Disposal

As with all nitroaromatic and halogenated heterocyclic compounds, appropriate precautions must be observed when working with 6-Chloro-3-nitroquinolin-4-ol. The following guidance is based on general principles for similar chemical classes; users must consult the Safety Data Sheet (SDS) supplied with SKU C189346 before use.

Personal Protective Equipment (PPE):

• Wear chemical-splash goggles, a lab coat, and nitrile gloves as a minimum.
• Work in a well-ventilated fume hood to avoid inhalation of dust or aerosols.

Storage:

• Store in a tightly sealed container in a cool, dry, well-ventilated area away from incompatible materials (strong oxidisers, strong bases).
• Recommended storage temperature: typically 2–8 °C or room temperature under inert atmosphere — confirm with the CoA/SDS for SKU C189346.
• Protect from light to prevent photodegradation of the nitro-containing aromatic compound.

Waste Disposal:

• Dispose of all waste in accordance with local, national, and institutional regulations governing halogenated organic waste.
• Do not discharge to sewer or waterways.

First Aid (general):

• Skin/eye contact: flush immediately with copious water for at least 15 minutes and seek medical attention.
• Inhalation: move to fresh air; seek medical attention if symptoms persist.

Ordering, Purity, and Quality Assurance

6-Chloro-3-nitroquinolin-4-ol is available from Aladdin Scientific under SKU C189346. Each batch is accompanied by a Certificate of Analysis (CoA) detailing purity, appearance, and analytical data obtained by methods such as HPLC, NMR, and/or elemental analysis.

Purity and grade: Specific purity grades and analytical specifications for SKU C189346 should be confirmed directly on the Aladdin Scientific product page or by contacting technical support. General reagent-grade quinoline derivatives typically have purities ≥95% (HPLC); however, users requiring higher purity for sensitive assays should request lot-specific CoA data before ordering.

Available pack sizes: Pack sizes vary; consult the current product listing for up-to-date stock and pricing information.

Ordering guidance:

• Quote SKU C189346 when placing orders to ensure correct product selection.
• For bulk or custom quantities, contact Aladdin Scientific sales or submit a custom-synthesis enquiry.
• International shipping of this compound may be subject to export regulations applicable to halogenated and nitroaromatic chemicals; confirm requirements with your procurement team.

Frequently asked questions

What solvents are recommended for dissolving 6-Chloro-3-nitroquinolin-4-ol?

Based on the general properties of nitroquinolinol compounds, DMSO and DMF are the most suitable solvents, offering moderate to good solubility. The compound is sparingly soluble in water and common protic solvents such as methanol or ethanol. Users should verify solubility data against the CoA provided with SKU C189346, as exact values were not available in the source material.

Can 6-Chloro-3-nitroquinolin-4-ol be used directly in palladium-catalysed cross-coupling reactions?

Yes, the C-6 aryl chloride is suitable for palladium-catalysed cross-coupling reactions, including Suzuki–Miyaura and Buchwald–Hartwig couplings, using appropriate ligands and bases. However, the nitro group and the acidic N–H or O–H may require protection or careful choice of reaction conditions to avoid side reactions. Specific optimised conditions are not available in the source material and should be established empirically or sourced from the literature on analogous substrates.

How should I store 6-Chloro-3-nitroquinolin-4-ol to ensure long-term stability?

Store the compound in a tightly sealed container, protected from light, moisture, and heat. A recommended storage temperature is 2–8 °C or as specified on the product CoA/SDS for SKU C189346. Keeping the material under an inert atmosphere (nitrogen or argon) after opening is advisable to minimise degradation. Always confirm specific storage conditions with the Aladdin Scientific CoA accompanying your lot.

Is 6-Chloro-3-nitroquinolin-4-ol the same as 6-chloro-3-nitro-1H-quinolin-4-one?

Yes. 4-Hydroxyquinolines exist in tautomeric equilibrium between the 4-hydroxy (enol) form and the 4-quinolinone (keto/lactam) form. In the solid state and in many solvents, the keto tautomer predominates, so both names refer to the same compound. The IUPAC preferred name and the tautomeric form present in your sample can be confirmed from the CoA for SKU C189346.

References

1. General reactivity of 4-hydroxyquinoline and nitroquinoline derivatives — textbook-level knowledge; no specific primary literature citation available in source material.
2. Aladdin Scientific product page for 6-Chloro-3-nitroquinolin-4-ol, SKU C189346 — consult for current CoA, SDS, pricing and availability.

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