1-Chloro-2-methyl-3,5-dinitrobenzene: FAQs & Lab Guide

1-Chloro-2-methyl-3,5-dinitrobenzene is a nitroaromatic halide used as a versatile electrophilic intermediate in organic synthesis, particularly in the preparation of substituted aniline derivatives and specialty agrochemical or pharmaceutical building blocks.

Chemical Name

1-Chloro-2-methyl-3,5-dinitrobenzene

CAS Number

5326-32-9 (needs_review)

Molecular Formula

C7H5ClN2O4

Molecular Weight

216.57 g/mol

Aladdin SKU

C727506

Compound Class

Nitroaromatic halide / synthetic intermediate

Typical Storage Condition

Cool, dry, well-ventilated location away from heat and ignition sources

What Is 1-Chloro-2-methyl-3,5-dinitrobenzene?

1-Chloro-2-methyl-3,5-dinitrobenzene is a substituted benzene ring bearing a chloro group at the 1-position, a methyl group at the 2-position, and nitro groups at the 3- and 5-positions. This combination of electron-withdrawing nitro substituents and an ortho methyl group imparts distinctive reactivity: the ring is strongly deactivated toward electrophilic aromatic substitution yet activated toward nucleophilic aromatic substitution (S_NAr) at the carbon bearing the chloro leaving group. The compound is therefore classified as a nitroaromatic halide and a synthetic intermediate of broad utility in fine-chemical manufacturing.

Its physical appearance is typically a pale yellow to off-white crystalline solid at room temperature. The presence of two nitro groups significantly raises the molecular weight (approximately 216.57 g/mol) relative to simple chlorotoluenes and contributes to the compound's relatively high melting point and low vapor pressure under ambient conditions.

Key Chemical Properties and Reactivity

Nucleophilic Aromatic Substitution (S_NAr): The two flanking nitro groups at the 3- and 5-positions strongly stabilize the Meisenheimer complex intermediate formed when a nucleophile attacks the ipso carbon. This makes the C–Cl bond susceptible to displacement by amines, alkoxides, thiolates, and other soft or hard nucleophiles under mild-to-moderate conditions. Researchers routinely exploit this reactivity to introduce diverse functional groups in a single step.

Reduction of Nitro Groups: The nitro substituents can be selectively or sequentially reduced to amino groups using catalytic hydrogenation (e.g., Pd/C, H₂) or chemical reductants (e.g., Fe/AcOH, SnCl₂). The resulting diamino or monoamino intermediates are valuable building blocks for dyes, pharmaceuticals, and agrochemicals.

Stability Considerations: As a polynitro compound, 1-chloro-2-methyl-3,5-dinitrobenzene may exhibit sensitivity to mechanical shock, heat, or friction at elevated concentrations. Bulk quantities must be handled with appropriate precautions. Review the Safety Data Sheet (SDS) before use.

Safe Handling, Storage, and Disposal

Personal Protective Equipment (PPE): Always wear nitrile or neoprene gloves, a lab coat, and chemical-splash safety goggles when handling this compound. For operations generating dust or aerosols, use a NIOSH-approved respirator and work within a chemical fume hood.

Storage: Store in a tightly sealed container in a cool (below 25 °C), dry, and well-ventilated storeroom. Keep away from oxidizers, open flames, and strong reducing agents. Label containers clearly with compound name, CAS number, and hazard warnings. Segregate from incompatible materials per applicable local regulations.

Disposal: Do not dispose of this compound via ordinary waste streams. Collect in appropriate solvent-waste or solid-waste containers designated for halogenated nitroaromatic waste. Arrange disposal through a licensed hazardous-waste contractor in compliance with local, national, and international regulations (e.g., RCRA in the US, CLP/REACH in the EU).

Consult the Aladdin SDS for complete hazard classifications, first-aid measures, and transport information before commencing work.

Typical Research Applications

1-Chloro-2-methyl-3,5-dinitrobenzene serves as a key electrophilic building block across multiple research domains:

• Pharmaceutical Intermediates: The activated aromatic chloride is a starting material or intermediate for constructing pharmacophores that incorporate diaminoaromatic or aminonitroaromatic scaffolds. Selective reduction of one nitro group followed by S_NAr or acylation allows convergent synthesis of complex targets.
• Agrochemical Synthesis: Nitroaromatic halides of this type appear in the synthesis of herbicide and fungicide candidates, where the methyl and nitro groups modulate lipophilicity and biological activity.
• Dye and Pigment Chemistry: Reduction of both nitro groups yields a diaminotoluene derivative that can be incorporated into azo-dye or polyurethane/polyurea chain-extender chemistry.
• Material Science: The compound can be used to introduce nitro or amino functionalities into polymer backbones or surface coatings via reactive incorporation.

Researchers should validate suitability for their specific application by consulting primary literature and conducting preliminary feasibility experiments.

Ordering, Specifications, and Quality

Aladdin SKU: C727506 — 1-Chloro-2-methyl-3,5-dinitrobenzene. Customers should reference this SKU when placing orders to ensure receipt of the correct material.

Available Specifications: Purity grade, pack size, and lot-specific analytical data (e.g., HPLC purity, NMR, melting point) vary by production lot. Contact Aladdin Scientific's technical or customer-service team for current Certificate of Analysis (CoA) data, bulk-pricing inquiries, or custom pack sizes.

Quality Assurance: Aladdin Scientific follows standard quality-control procedures for research-grade reagents. Each lot is accompanied by a CoA indicating purity and key physical constants. If your application demands ultra-high purity or specific impurity profiles, discuss custom specifications with our team before ordering.

Lead Times and Shipping: This compound is typically shipped as a solid at ambient temperature with appropriate hazardous-material labeling. International shipments are subject to export-control and import-permit requirements depending on destination country. Contact customer service for regional availability and estimated delivery timelines.

Frequently asked questions

What nucleophiles react well with 1-Chloro-2-methyl-3,5-dinitrobenzene under SᵎAr conditions?

Primary and secondary aliphatic amines, aromatic amines, alkoxides, and thiolates are all effective nucleophiles for displacing the chloro leaving group via SᵎAr. The reaction typically proceeds in polar aprotic solvents such as DMF, DMSO, or acetonitrile, often without requiring a metal catalyst. Reaction temperature and stoichiometry should be optimized for each specific nucleophile.

How should I store 1-Chloro-2-methyl-3,5-dinitrobenzene to ensure long-term stability?

Store the compound in a tightly sealed container in a cool (below 25 °C), dry, and well-ventilated area, away from heat sources, open flames, and incompatible materials such as strong oxidizers or reducing agents. When stored under these conditions, the crystalline solid is expected to remain stable for an extended period; however, always check the lot-specific expiry or re-test date on the CoA and retest if stability is in question.

Can the nitro groups in 1-Chloro-2-methyl-3,5-dinitrobenzene be selectively reduced to give monoamino products?

Selective mono-reduction is possible but challenging due to the similar electronic environments of the two nitro groups at the 3- and 5-positions. Partial reduction using controlled amounts of reductant (e.g., Na₂S, limited H₂ with Pd/C) or carefully optimized catalytic transfer hydrogenation conditions can favor mono-reduction, but full reduction to the diamine is often the dominant outcome under standard conditions. Reaction optimization and careful monitoring by TLC or HPLC are recommended.

Is 1-Chloro-2-methyl-3,5-dinitrobenzene considered hazardous for shipping purposes?

As a polynitro aromatic compound, this material is likely subject to hazardous-goods regulations for transport (e.g., IATA for air, IMDG for sea, ADR for road in Europe). The specific UN number, packing group, and hazard class should be confirmed from the current SDS before arranging shipment. Aladdin Scientific's customer-service team can advise on shipping options and regional restrictions.

What analytical methods are recommended to confirm the purity of 1-Chloro-2-methyl-3,5-dinitrobenzene?

Reverse-phase HPLC with UV detection (typically at 254 nm or 300–350 nm, where nitroaromatics absorb) is the most common quantitative purity method. Complementary techniques include melting-point determination (compared against literature values), ¹H NMR spectroscopy to confirm substitution pattern and absence of isomeric impurities, and GC for volatile impurity profiling. Aladdin's CoA documents the purity method used for each lot.

References

1. March, J. Advanced Organic Chemistry: Reactions, Mechanisms, and Structure, 4th ed. Wiley, 1992. (General reference for SᵎAr reactivity of activated aryl halides.)
2. Clayden, J.; Greeves, N.; Warren, S. Organic Chemistry, 2nd ed. Oxford University Press, 2012. (Nucleophilic aromatic substitution and nitro-group reduction chapters.)
3. Aladdin Scientific Product Page: 1-Chloro-2-methyl-3,5-dinitrobenzene, SKU C727506. https://www.aladdin-e.com (accessed 2024).

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