meta-Dinitrobenzene 1,3-Dinitrobenzene · CAS 99-65-0

What is meta-Dinitrobenzene?

meta-Dinitrobenzene, also called 1,3-dinitrobenzene, is a benzene ring carrying two nitro groups at the 1- and 3-positions, formula C₆H₄N₂O₄. It is supplied as pale yellow to orange flakes or powder.

It is the dominant isomer formed when nitrobenzene is dinitrated, since the nitro group already on the ring directs further nitration almost entirely to the meta-position. That makes meta-Dinitrobenzene the by-far most commercially available dinitrobenzene isomer, and the one on which most downstream dinitrobenzene chemistry is built.

Commercially it is produced by dinitrating nitrobenzene (or benzene) with mixed acid under controlled temperature, then purifying the product by crystallisation.

Handling follows precautions appropriate to an acutely toxic, skin-absorbed material — impervious chemical-resistant gloves and clothing, eye protection, adequate ventilation, and storage away from incompatible materials such as strong oxidisers, caustics and certain metals.

Why meta-Dinitrobenzene specifically

• The principal route to m-phenylenediamine. Reduction of meta-Dinitrobenzene is the standard industrial path to m-phenylenediamine (MPDA), itself a major azo-dye and pigment intermediate.
• The dominant, most available isomer. Nitration chemistry naturally favours the meta-substitution pattern, making this isomer the commercial default.
• A building block for high-performance polymers. MPDA derived from this material underpins aramid fibres and epoxy-resin curing agents.
• Not interchangeable with the ortho- or para-isomer. The 1,2- and 1,4-dinitrobenzene isomers have different physical properties and are supplied for different, narrower applications.

How meta-Dinitrobenzene is Manufactured

meta-Dinitrobenzene is produced by dinitrating nitrobenzene (or, less commonly, benzene directly) with mixed acid under controlled temperature.

• Dinitration. Nitrobenzene is nitrated a second time with mixed acid; the existing nitro group directs substitution almost entirely to the meta-position.
• Quench and separation. The crude product is separated from the spent acid phase and washed.
• Purification. The product is purified by crystallisation to the target assay and melting-point specification.
• Quality release and packing. Assay, melting point and appearance are confirmed against specification before the batch is packed and released.

Typical Commercial Specification

Figures below are representative of commercial-grade meta-Dinitrobenzene. Tell us your downstream route and the grade you need, and we will advise on the specification to order against.

Physical & Chemical Properties

Behaviour in the process

meta-Dinitrobenzene's reactivity pattern is what dye and polymer intermediate producers are buying:

• Reducible nitro groups. Both nitro groups are available for reduction, most importantly to m-phenylenediamine.
• Combustible solid. Stable under normal storage but, like other dinitrobenzene isomers, reacts vigorously with strong oxidising materials; keep well away from them.
• Volatile with steam. Relevant to how spills and residues are handled and cleared from process equipment.

meta-Dinitrobenzene and Related Nitroaromatics

Choosing between dinitrobenzene isomers and related nitroaromatics comes down to the substitution pattern the target synthesis needs.

Stated plainly: most commercial dinitrobenzene demand is for the meta-isomer — the ortho- and para-isomers are produced in much smaller volumes and supplied for narrower, specific applications.

Industries We Supply meta-Dinitrobenzene To

The same dinitrobenzene isomer feeds a dye-intermediate manufacturer producing m-phenylenediamine and a polymer or specialty-chemical producer building on that same amine. What changes is the downstream reduction and derivatisation chemistry and the documentation each requires.

Where meta-Dinitrobenzene is Used

In downstream functionalisation

meta-Dinitrobenzene's two nitro groups are carried through reduction to build m-phenylenediamine, which is then taken forward into azo-coupling, condensation or polymerisation chemistry depending on the end product. The meta-substitution pattern is what makes this specific isomer, rather than the ortho- or para-forms, the industry's default feedstock.

Quality Control & Testing

Every lot is released against a batch-specific Certificate of Analysis, with melting point and isomer purity reported alongside the main assay because ortho- and para-dinitrobenzene carryover affects downstream reduction selectivity and product colour.

• meta-DNB content — by GC or HPLC assay, the primary grade measure.
• Isomer purity — ortho- and para-dinitrobenzene carryover, reported because it affects downstream chemistry.
• Melting point — reported because it is a sensitive indicator of overall purity for this material.

Common Process Problems & Likely Causes

Packaging, Storage & Shipping

• Standard packing. Multi-ply paper or HDPE-lined bags and fibre drums, typically 25 kg net, with bulk-bag formats on contract supply.
• Combustible-solid precautions. Store away from ignition sources, open flame and strong oxidisers; follow local fire-code requirements for a combustible nitroaromatic solid.
• Temperature control. Store in a cool, dry, well-ventilated area away from direct sun and heat.
• Material compatibility. Avoid contact with strong oxidisers, caustics and certain metals such as tin and zinc.
• Transport classification. Commonly shipped under UN 1597, Class 6.1, packing group II. Confirm the correct entry and packing group against your own current SDS before shipping.

Hazards & Safe Handling

meta-Dinitrobenzene is fatal if swallowed, in contact with skin or if inhaled, and is very toxic to aquatic life with long-lasting effects. It is readily absorbed through intact skin, which is the primary route of occupational exposure, and can cause methaemoglobinaemia (reduced oxygen-carrying capacity of the blood), liver damage and effects on the eyes and central nervous system. Standard precautions for a highly toxic nitroaromatic and strict good laboratory and plant practice apply throughout handling.

• Skin and eye contact. Impervious chemical-resistant gloves and clothing and splash goggles are essential; this material is significantly absorbed through intact skin. Rinse thoroughly with water on contact and seek medical attention.
• Inhalation. Use closed handling or adequate local exhaust ventilation, particularly where dust is generated.
• PPE. Impervious chemical-resistant gloves and clothing, chemical splash goggles and, where dust exposure is a concern, a suitable respirator.
• Environment. Very toxic to aquatic life with long-lasting effects; avoid uncontrolled release to water and follow local effluent rules.

Regulatory & Compliance Notes

meta-Dinitrobenzene is a long-registered, widely used nitroaromatic intermediate. Because obligations differ by territory and use, the notes below are orientation rather than legal advice.

• GHS classification. Classified as fatal if swallowed, in contact with skin or if inhaled, and very toxic to aquatic life with long-lasting effects (Signal word: Danger); the SDS carries the full hazard statements and occupational exposure limits for your grade.
• Occupational exposure limits. Recognised occupational exposure limits for m-dinitrobenzene are set very low, with a skin-absorption notation in most jurisdictions — confirm the limit that applies in your facility's territory.
• REACH and chemical inventories. Registered under EU REACH and listed on major chemical inventories.
• Dangerous goods transport. Commonly shipped under UN 1597 (Dinitrobenzenes), Class 6.1, packing group II. Confirm the correct entry and packing group with your logistics/EHS team against your current SDS before shipping.
• HS code. Commonly declared under the nitro-derivatives-of-hydrocarbons heading; confirm the exact tariff line with your customs broker for your jurisdiction.

We Supply meta-Dinitrobenzene Worldwide

Chelora Chemicals is a supplier and export partner, not a single-plant trader. We ship meta-Dinitrobenzene from India and from partner sources to customers across Asia, Europe, the Middle East, Africa, and North and South America, handling the export documentation and freight so the material arrives ready to use.

• Incoterms. EXW, FOB, CIF, CFR and DAP quoted to suit your purchasing terms and freight arrangements.
• Ports. Regular shipments through Nhava Sheva (JNPT) and Mundra, with other ports arranged as routing allows.
• Documentation. Commercial invoice, packing list, certificate of origin, COA and SDS issued as a complete set.
• Flexible volumes. From trial quantities up to repeat bulk shipments on a supply contract.

Buying meta-Dinitrobenzene from Chelora

We are an independent sourcing and supply partner. For this product that means settling three things at enquiry: the purity and isomer-purity grade your application needs, the packing format, and the quantity you are buying.

• Documentation on every lot. Batch-specific COA with assay, melting point and isomer breakdown, plus the current SDS.
• Analysis before commitment. Representative analysis shared ahead of a commercial order so your lab can qualify the material.
• Quantities. Trial quantities through to larger bulk shipments on contract supply.
• Inspection. Independent third-party inspection available at loading when the contract requires it.
• Related nitroaromatics. 2,5-Dichloro Nitro Benzene and other nitro and chloronitro intermediates alongside this product from one supplier.

How ordering works

• Send the enquiry. Purity, isomer-purity grade, quantity, destination port and the Incoterm you buy on.
• We quote. Price, lead time, packing format and a sample COA, normally within one working day.
• Qualify the supply. For first orders or colour-sensitive applications, we share the analysis so your technical team can sign off before you commit.
• Confirm the order. Proforma invoice issued; payment terms agreed against the volume and the relationship.
• Ship and document. Packed, labelled and loaded with the full export document set, and tracked through to arrival.

Related Nitroaromatic Intermediates