2,4-Dinitroaniline
2,4-Dinitroaniline is a dinitro-substituted aniline used almost exclusively as the diazo component in Pigment Orange 5, a widely produced azo pigment — a commercial identity distinct from, and not to be confused with, the unrelated dinitroaniline-class herbicides that share only a generic chemical family name.
What 2,4-Dinitroaniline is, and why buyers source it
A working overview of the compound's chemistry, its place in the aniline-derivative family, and the grades Chelora Chemicals keeps in regular supply.
We want to be clear about what this compound is used for, because its name invites a specific and understandable mix-up. "Dinitroaniline" is also the generic name for an entire herbicide chemical class (trifluralin, pendimethalin, and similar actives), and a buyer searching for dinitroaniline chemistry can land on this page expecting an agrochemical active. 2,4-Dinitroaniline (CAS 97-02-9) is not one of those herbicide actives — the dinitroaniline herbicides are built on a different, more heavily substituted core (typically a trifluoromethyl-substituted toluidine backbone), not on this simple 2,4-disubstituted aniline. This compound's real, documented commercial identity is as a dye and pigment intermediate.
Specifically, diazotisation of the free amino group on 2,4-Dinitroaniline, followed by coupling with 2-naphthol, produces Pigment Orange 5 (also known as Permanent Orange, CI 12075) — a long-established, moderately priced azo pigment used in printing inks, paints, plastics, and other colourant applications. This is a well-documented, single, specific end use, not a diversified chemical-intermediate platform the way some other building blocks in our range are.
Where it fits in the synthesis chain
We supply the dinitroaniline intermediate; we do not manufacture or supply the finished Pigment Orange 5 pigment. We also do not supply, and have no involvement with, any dinitroaniline-class herbicide active — buyers interested in that different chemistry should source directly from an agrochemical active-ingredient manufacturer and reference the correct CAS number for the specific herbicide they require.
Grades we supply
98% min pigment-intermediate grade is the standard offering; colour value and residual mono-nitro/isomeric impurity are tracked as the properties most directly affecting the shade and strength of the coupled pigment.
How 2,4-Dinitroaniline is made
An overview of the production route for orientation purposes. Our manufacturing partners' own process parameters and in-process controls are proprietary and are not disclosed beyond what is needed to interpret the certificate of analysis.
2,4-Dinitroaniline is manufactured by direct dinitration of aniline, or more commonly by ammonolysis of 2,4-dinitrochlorobenzene (DNCB) — reacting it with ammonia under controlled conditions to displace the chlorine and install the amino group. The ammonolysis route is the industrially preferred path, because direct dinitration of free aniline is difficult to control and gives poor selectivity, for the same reason direct nitration of aniline is avoided in the mononitroaniline products in our range.
The ammonolysis reaction is typically run in aqueous ammonia or an ammonia/alcohol mixture at moderate temperature and pressure; the electron-withdrawing effect of the two nitro groups already present on the ring makes the chlorine in DNCB considerably more reactive toward nucleophilic displacement than a mono-nitro or unsubstituted chloroarene, so this substitution proceeds under notably milder conditions than the equivalent mononitro reaction.
The crude product is isolated by cooling and filtration, then purified by recrystallisation — typically from an alcohol/water mixture — to remove unreacted DNCB and isomeric dinitroaniline impurities. Colour value and melting point (177–180°C) are the standard release checks; because the compound's sole commercial use is as a pigment-coupling intermediate, purity specification is built around what affects coupled-pigment shade and strength rather than around broader chemical-intermediate criteria.
A note on this compound and energetic materials
Because this molecule carries two nitro groups, it is reasonable to ask whether it falls into energetic-materials or explosives-related chemistry. It does not: 2,4-Dinitroaniline is a well-characterised, non-explosive, UN-regulated-as-toxic (not as an explosive) commercial dye-and-pigment intermediate, and its entire documented industrial use is azo-pigment coupling chemistry. We supply it strictly on that commercial basis, for buyers in the pigment, ink, and colourant industries, and we apply standard end-use screening consistent with that use.
Industries and processes that use it
2,4-Dinitroaniline is consumed almost entirely as a synthesis intermediate. The four fields below account for most of the demand we see through our export desk.
Pigment Orange 5 Synthesis
Diazotisation of the amino group followed by coupling with 2-naphthol produces Pigment Orange 5 (CI 12075, also called Permanent Orange), a widely used azo pigment.
Printing Ink Colourants
Pigment Orange 5 made from this intermediate is used in printing inks where a moderately priced, lightfast orange shade is required.
Paint & Plastics Colourant Chemistry
The same pigment chemistry extends into paint and plastics colourant formulation, wherever an azo-based orange pigment fits the cost and performance requirement.
General Azo Dye Intermediate Research
Used in smaller volumes in academic and specialty dye-chemistry work as a diazo component with distinctive, strongly electron-withdrawing ring substitution.
How the molecule is typically carried forward
2,4-Dinitroaniline's reaction chemistry is dominated by a single, well-defined transformation: diazotisation of the amino group for pigment coupling. The two nitro groups are present as powerful electron-withdrawing substituents that shape the reactivity of the amine, rather than as independently reactive sites in their own right at this stage.
Diazotisation of the amino group
Standard cold nitrous-acid diazotisation converts the amino group to a diazonium salt. The two electron-withdrawing nitro groups make this amine notably less basic and the resulting diazonium salt correspondingly more electrophilic than that of an unsubstituted aniline, which is part of why this chemistry is reliable and well-controlled industrially.
Azo coupling with 2-naphthol
The diazonium salt couples with 2-naphthol under standard alkaline coupling conditions to form the azo linkage that constitutes Pigment Orange 5. This is the sole large-scale downstream reaction this compound is known for.
Why further nitration or reduction is not practiced
Because the pigment-coupling route already uses the amino group efficiently and the dinitro-substitution pattern is exactly what gives Pigment Orange 5 its characteristic shade, there is no commercial driver to reduce the nitro groups or add further substitution — unlike the mononitroanilines, where reduction to a diamine opens up an entirely separate commercial chain.
2,4-Dinitroaniline against its near relatives
2,4-Dinitroaniline is the only dinitro-substituted member of the nitroaniline family in our range, set apart from the mononitroanilines by a second nitro group that both raises its melting point substantially and gives it a single, well-defined commercial identity in pigment chemistry.
| Product | CAS Number | Typically Used In | Notes |
|---|---|---|---|
| 2,4-Dinitroaniline | 97-02-9 | Pigment Orange 5 intermediate | The product on this page. mp 177–180°C. |
| Ortho Nitroaniline | 88-74-4 | o-Phenylenediamine → benzimidazole fungicides | Also supplied — see its product page. mp 71–72°C. |
| Para Nitroaniline | 100-01-6 | p-Phenylenediamine → Para Red pigment chemistry | Also supplied — see its product page. mp 147–148°C. |
| Aniline | 62-53-3 | Parent amine for the entire product range | The unsubstituted parent compound — see its product page. |
Exact physical constants and purity specifications are confirmed per batch on the certificate of analysis — treat the notes above as a sourcing guide rather than a specification sheet.
Safety classification at a glance
Based on GHS classification as commonly listed for this substance. This is a summary for orientation only — always work from the current safety data sheet supplied with your specific batch.
Harmful if swallowed.
Harmful in contact with skin.
Harmful if inhaled.
May cause an allergic skin reaction.
Very toxic to aquatic life.
Very toxic to aquatic life with long lasting effects.
Warning
2,4-Dinitroaniline carries no harmonised CMR classification under EU CLP Annex VI, and IARC has not evaluated this compound. It is transported and regulated as UN 1596, Class 6.1 (toxic solid) — a toxicity classification, not an explosives classification — consistent with its status as a non-energetic commercial intermediate. Its hazard profile combines acute oral/dermal/inhalation toxicity, documented skin-sensitisation potential, and pronounced aquatic toxicity (H400/H410), broadly in line with the mononitroaniline compounds in our range but at a somewhat higher acute-toxicity category reflected on some supplier SDSs — we recommend checking the classification on the specific SDS version shipped with each lot.
Keeping it on spec between delivery and use
General storage guidance for this grade. Site-specific storage rules, segregation requirements and re-test intervals should follow your own EHS procedures and the MSDS issued with your batch.
Store in a cool, dry, well-ventilated area away from strong oxidising and reducing agents, open flame, and sources of ignition, consistent with standard practice for nitroaromatic solids. Keep containers tightly sealed and protect from prolonged light exposure.
How it ships from Indonesia
Standard packing and export terms for this product. Confirm exact figures against your order — they vary slightly by destination and quantity.
What travels with every batch
Specification is agreed before the purchase order, not discovered on arrival. Every shipment of 2,4-Dinitroaniline leaves with a documented, checkable paper trail.
Certificate of Analysis
Batch-wise assay (by GC), isomer purity, melting point range and moisture, issued against the agreed specification so your QC team can check it, not just file it.
Safety Data Sheet
GHS-format SDS in English covering hazard classification, handling, storage, first-aid and spill response for the exact grade shipped.
Technical Data Sheet
Reference physical and chemical properties, recommended storage and typical applications, for internal circulation to your process or R&D teams.
Certificate of Origin
Confirms Indonesian origin for customs clearance and any preferential-duty claim at your destination port.
Dangerous Goods Declaration
UN packing group, classification and shipper's declaration prepared ahead of loading so documentation never holds up customs.
Third-Party Inspection
Independent pre-shipment inspection and re-sampling can be arranged on request, at your cost, for buyers who require it as a matter of policy.
Frequently asked questions
What buyers most often ask our sales desk about this grade.
01What is 2,4-Dinitroaniline used for?+
02What is the CAS number of 2,4-Dinitroaniline?+
03What purity grades does Chelora Chemicals supply?+
04Is 2,4-Dinitroaniline hazardous?+
05Is this the same chemistry as dinitroaniline herbicides like trifluralin?+
06Does the double nitro-group substitution make this an explosive or energetic material?+
07Do you supply the finished Pigment Orange 5 pigment?+
08What packing options are available?+
09How long does delivery take?+
10Can I get a sample before placing a bulk order?+
11How is 2,4-Dinitroaniline manufactured?+
12What is the shelf life, and how should it be stored?+
Need 2,4-Dinitroaniline on spec, on time?
Send us your required purity, quantity, packing preference and destination port. Our desk quotes most enquiries within one working day.