2,3,4-Trichloronitrobenzene
2,3,4-Trichloronitrobenzene — TCNB — is a nitro-chlorinated aromatic intermediate best known as the starting material for third-generation fluoroquinolone antibacterial drugs such as lomefloxacin and ofloxacin, and for the synthesis of the herbicide aclonifen. It also serves general dye, pigment and fine chemical synthesis wherever the 2,3,4-trichlorophenyl fragment is required.
Chelora Chemicals supplies TCNB to pharmaceutical intermediate manufacturers, agrochemical formulators and fine chemical producers worldwide, in drums and container quantities, with a batch COA and GHS safety data sheet on every consignment.
Product identity
- CAS Number
- 17700-09-3
- IUPAC name
- 1,2,3-Trichloro-4-nitrobenzene
- Molecular formula
- C6H2Cl3NO2
- Molecular weight
- 226.44 g/mol
- EC / EINECS
- 241-705-5
- MDL number
- MFCD00007063
- SMILES
- [O-][N+](=O)c1ccc(Cl)c(Cl)c1Cl
- HS Code
- 2904 20*
* Confirm the exact HS heading with your customs broker — classification of nitro-chlorinated aromatics varies between destination tariffs.
What 2,3,4-Trichloronitrobenzene is used for
2,3,4-Trichloronitrobenzene combines a nitro group with three adjacent ring chlorines on the same benzene ring. That combination makes it an activated substrate for nucleophilic aromatic substitution at the chlorines and a straightforward substrate for reduction of the nitro group to an aniline — the two reactions that carry it into almost every downstream product built from it.
In practice TCNB is almost entirely a captive pharmaceutical and agrochemical intermediate. Its best-documented outlet is as the starting material for third-generation fluoroquinolone antibacterial drugs — including lomefloxacin and ofloxacin — where the trichloronitrobenzene core is built into the quinolone ring system. It is also the recognised starting material for the diphenyl-ether herbicide aclonifen, and finds general use in dye, pigment and fine chemical synthesis.
Why the substitution pattern matters
Trichloronitrobenzene exists as several positional isomers, and pharmacopoeial and agrochemical routes are built around one specific pattern:
- 2,3,4-Trichloronitrobenzene (CAS 17700-09-3) — this product, also named 1,2,3-trichloro-4-nitrobenzene. Three chlorines adjacent to one another, nitro group para to one of them. The pharmaceutical- and agro-relevant isomer.
- 2,4,6-Trichloronitrobenzene — a different substitution pattern studied in its own right, including in comparative toxicology work; not interchangeable in synthesis.
- 3,4,5-Trichloronitrobenzene — another positional isomer with its own chemistry and toxicological profile.
If your purchase order simply says "trichloronitrobenzene", quote us the CAS number and we will confirm the correct material before the order is placed. We also supply the precursor 1,2,3-trichlorobenzene and other nitro-chlorinated aromatics — see our full product range.
Appearance and handling character
TCNB ships as a white to light yellow, sometimes yellow-brown, crystalline solid or powder melting in the roughly 51–58 °C range reported across commercial suppliers — a solid in a temperate store, but liable to soften in an uncooled container on a tropical routing. It is essentially insoluble in water and dissolves in common organic solvents such as acetone, chloroform and toluene. As with other nitro aromatics it should be regarded as an oxidiser-sensitive solid and handled accordingly — read the safety section before planning storage or transfer.
| Parameter | Typical value |
|---|---|
| Appearance | White to light yellow powder or crystals |
| Assay (HPLC/GC) | 98.0% min |
| Moisture | 1.0% max |
| Melting range | 51 – 58 °C |
| Total isomeric impurities | 1.5% max |
| Infrared / NMR | Conforms to structure |
Important: the figures above are indicative of commercial grade material and are offered for planning only. The batch certificate of analysis is the governing document. If your synthesis route demands a tighter assay, a narrower melting range or a specific isomer limit, send us the specification and we will quote against it rather than against a generic grade.
| Property | Value |
|---|---|
| Physical state | Crystalline solid / powder at ambient |
| Melting point | ≈ 51 – 58 °C |
| Molecular weight | 226.44 g/mol |
| Water solubility | Essentially insoluble |
| Organic solubility | Soluble in acetone, chloroform, toluene |
| Appearance on storage | May darken toward yellow-brown |
| Odour | Faint, aromatic/nitro-like |
Physical constants compiled from public reference and vendor data for CAS 17700-09-3 and rounded for readability; individual analytical certificates vary within this range. Treat them as orientation, not as a specification.
Where our customers put this molecule to work
TCNB is a specialty intermediate with a small number of well-documented, high-value outlets rather than a broad commodity market — which is exactly why sourcing discipline and specification control matter so much.
Fluoroquinolone antibacterials
TCNB is the recognised starting material for building the quinolone core used in third-generation fluoroquinolone antibacterial drugs, including lomefloxacin and ofloxacin. Purity and isomeric consistency at this stage carry through the entire multi-step synthesis.
- Quinolone ring-system construction
- Assay and isomer limits are typically strict
- Batch traceability expected by pharma buyers
Aclonifen herbicide synthesis
2,3,4-Trichloronitrobenzene is the established starting material for aclonifen, a diphenyl-ether herbicide used in a range of broadleaf and grass-weed control programmes.
- Diphenyl ether herbicide chemistry
- Nitro reduction and ether-coupling steps downstream
- See our agrochemical intermediate range
Dye & pigment synthesis
Reduction of the nitro group gives 2,3,4-trichloroaniline, which can be carried into azo and other colourant chemistry wherever the trichlorophenyl fragment is the target structure.
- Nitro-to-amine reduction route
- Feeds azo and related colourant chemistry
- Consistent isomer purity avoids off-shade product
Nucleophilic substitution chemistry
The activated ring chlorines, flanked by the electron-withdrawing nitro group, support nucleophilic aromatic substitution for custom ether, amine and thioether intermediates in fine chemical synthesis.
- SNAr chemistry at the activated chlorine
- Custom substitution for bespoke intermediates
- Available in trial and laboratory quantities
Analytical & reference standards
TCNB is also supplied as a certified reference material and analytical standard for environmental and residue-testing laboratories working on chlorinated nitroaromatic analysis.
- Solution and neat reference-material grades
- COA-backed traceability for lab use
- Small-pack and solution formats available
Contract & scheduled supply
Pharmaceutical intermediate and active-ingredient plants run to campaign, not to a calendar month. We hold contracted tonnage and release it against your production schedule rather than in one shipment.
- Annual contracts with scheduled call-off
- Price held across the contract period
- Second source held in reserve
How we supply 2,3,4-Trichloronitrobenzene
Chelora Chemicals is a supplier and sourcing partner, not a manufacturer. We own no nitration plant — and for a pharmaceutical- and agrochemical-grade intermediate like this one, that independence works in your favour. We are never obliged to push you whatever a captive unit happens to be running that month.
Instead we place your order with whichever qualified producer best matches your assay, your isomer tolerance, your price point and your delivery window.
We keep a second qualified source on this line. When a plant goes down for maintenance, or a monsoon disrupts a road corridor, your campaign switches source rather than stalling.
- Specification read against the CAS first. We confirm you need 17700-09-3 and not the 2,4,6- or 3,4,5- isomer before we quote a price.
- Batch COA shared before dispatch. You approve the assay, melting range and impurity profile against your own spec while the material is still in our warehouse.
- Hazard status stated up front. This material is classified as harmful by inhalation, skin contact and ingestion, and irritating to eyes, skin and the respiratory system. We say so at enquiry stage — not in the small print of a document pack that arrives with the goods.
- Pre-shipment samples for qualification. New account or new source, your R&D team runs a lab batch before the full quantity ever moves.
- Packing chosen for your climate. With a melting point in the low-to-mid 50s °C, pack format and stowage matter on a tropical routing. We plan both with you.
- Export machinery handled in-house. Hazard classification, UN-approved packing, labelling, freight booking and customs paperwork are ours to manage.
- Consolidation onto one bill of lading. Ship TCNB alongside 1,2,3-trichlorobenzene and other intermediates from our range — one invoice, one shipment, one counterparty.
Packed the way your plant receives it
Pack format drives your landed cost and your handling effort — and for a material with a documented irritant and inhalation-hazard profile, it also drives operator exposure. Tell us how it will be charged at your end and we will quote the format that suits your operation.
Multi-wall paper & PE bags
Laminated multi-wall bags with an inner liner, palletised and shrink-wrapped. The default for LCL movements and for plants charging batch-wise by hand.
Fibre & HDPE drums
UN-certified drums with liner for longer sea transits and humid destinations. Preferred by pharmaceutical-intermediate buyers for lot integrity and lower contamination risk.
Jumbo / FIBC bags
Bulk bags with liner for high-volume users with mechanical charging. Fewer handling movements, lower operator contact and materially lower packing cost per kilo.
Samples, standards & trial packs
Laboratory samples, analytical-standard solutions and pilot quantities dispatched by courier so your R&D or QC team can qualify the grade before committing to campaign volume.
Incoterms to suit you
Quoted on the Incoterm your purchasing team works to. Ocean, air and road freight arranged end-to-end with documentation filed before booking.
Campaign despatch
Pharmaceutical intermediate and agrochemical production runs to campaign. We hold contracted tonnage and release it against your production calendar instead of landing it all at once.
Handle this as a harmful, irritant nitroaromatic
This is the point on the page that matters most. 2,3,4-Trichloronitrobenzene is harmful by inhalation, in contact with skin and if swallowed, and is irritating to the eyes, respiratory system and skin. Mutation data has been reported for the compound in the published literature, which is a reason to treat exposure control as a priority rather than an afterthought. The summary below is orientation only — the safety data sheet supplied with your consignment is the authoritative document and should govern your risk assessment, PPE selection, exposure monitoring and emergency planning.
Classified hazards
R20/21/22Harmful by inhalation, in contact with skin and if swallowed.R36/37/38Irritating to eyes, respiratory system and skin.S26In case of contact with eyes, rinse immediately with plenty of water and seek medical advice.
Hazard information reflects risk- and safety-phrase classification commonly published for CAS 17700-09-3 under legacy EU chemical-safety schemes. GHS-format classification can differ by supplier; always read the SDS issued with your specific batch, and treat the irritation and inhalation-hazard entries as the ones that shape your controls.
Spill & emergency orientation
Plan your response before the pallet arrives, not after a bag splits. The points below are orientation for your emergency planners — sections 4, 5 and 6 of the SDS are the authoritative instructions and should be posted at the point of use.
- Sweep, do not hose. Collect spilled solid mechanically into a labelled container; avoid washing nitroaromatic residues to a drain.
- Suppress dust. Dry sweeping of a fine solid generates an inhalable aerosol — use vacuum collection or dampen carefully in line with the SDS.
- Assume skin and eye contact is irritating. Gloves, goggles and coveralls should be on before any transfer, not fetched after a spill.
- Have the SDS with the casualty. The treating clinician needs the product identity and CAS number in hand for any exposure incident.
- Keep away from heat and decomposition sources. On thermal decomposition, nitroaromatics can emit toxic oxides of nitrogen and chlorine — do not incinerate without appropriate scrubbing.
Storage
- Cool, dry, well-ventilated store, away from direct sunlight and heat sources. The melting range starts around 51 °C, so an uncooled store in a hot climate can soften or partially fuse the contents.
- Keep containers tightly closed. This limits moisture pick-up and the gradual colour drift some batches show toward yellow-brown.
- Segregate from reducing agents, strong bases and combustibles. As a nitroaromatic, it should be kept apart from materials that could drive an exothermic reaction under heat or contamination.
- Access-controlled storage, consistent with a harmful, irritant classification.
- Shelf life is typically 24 months in sealed original packing under these conditions. Re-assay before use after long storage.
Handling & PPE
- Minimise dust and vapour generation. Closed transfer and mechanical charging where practical, particularly when breaking a caked drum or emptying a bulk bag.
- Skin and eye protection are the priority. Chemical-resistant gloves, goggles and coveralls, given the documented skin and eye irritation and the harmful-by-skin-contact classification.
- Respiratory protection where dust may be generated, given the harmful-by-inhalation classification — assess per your own exposure monitoring.
- Good occupational hygiene. No eating, drinking or smoking in the handling area; wash thoroughly before breaks and at the end of a shift.
- Avoid uncontrolled discharge to the environment, as a matter of good practice for a nitro-chlorinated aromatic even where no specific aquatic-hazard statement is on your current SDS.
Transport
TCNB is generally supplied and shipped as a non-regulated or lightly regulated solid at the small package sizes typical of analytical and R&D use, but bulk commercial shipments should always be classified against the current SDS and destination regulation rather than assumed. We classify each consignment, apply appropriate packaging and labelling, and file any required dangerous-goods declaration before the booking is made — ask us for the current shipping paperwork when you plan the shipment.
What travels with every consignment
A chemical shipment is only as good as the file that travels with it. Verifying what the source plant sends is precisely the work you are buying from a supplier — and for a pharmaceutical-facing intermediate, traceability is not optional.
Certificate of Analysis
Batch-specific assay, melting range, appearance and impurity profile — including a IR/NMR structure-conformity check where required — before we release the goods.
Safety Data Sheet
Full-format SDS covering hazards, exposure controls, handling, storage, spill response, toxicology and disposal — issued in the language your destination requires.
Shipping & DG documentation
Correct hazard classification, packaging and labelling for the destination, with any required dangerous-goods declaration prepared and filed before the container is booked.
Certificate of Origin
Chamber-attested where required, plus preferential-origin forms where a trade agreement gives your import duty relief at the destination.
Third-party inspection
SGS, Intertek or Bureau Veritas sampling and inspection arranged on request before loading, giving you independent verification of what actually ships.
Retained & pre-shipment samples
Pre-shipment samples carry the same COA as the commercial lot, so what your laboratory qualifies is exactly what arrives. Retention samples held against the batch.
The two doors out of this nitroaromatic
Almost everything made from TCNB leaves by one of two doors: reduction of the nitro group, or nucleophilic substitution at one of the activated chlorines. The routes below are the general industrial pattern, not a process disclosure.
Start with the nitration
1,2,3-Trichlorobenzene is nitrated under controlled mixed-acid conditions to install the nitro group and give the 2,3,4-trichloronitrobenzene core.
Door one — reduce
Catalytic or chemical reduction of the nitro group gives 2,3,4-trichloroaniline, a building block for quinolone antibacterial synthesis and azo colourant chemistry.
Door two — substitute
The nitro group activates the ring chlorines toward nucleophilic aromatic substitution, opening ether, amine and thioether routes used in herbicide and fine-chemical synthesis.
Finish to grade
The crude product is crystallised, washed and dried, then standardised to whatever the end market demands — pharmacopoeial-grade purity, agro spec or research-grade reference standard.
Why isomeric purity carries through the whole route
Both doors act on a molecule whose reactivity depends precisely on where the three chlorines and the nitro group sit relative to one another. Anything in the feed that carries a different substitution pattern follows the material down the line:
- Positional isomers (2,4,6- or 3,4,5-trichloronitrobenzene) reduce or substitute at different positions, giving a structurally similar but pharmacologically or agronomically distinct byproduct.
- Residual moisture and acid can interfere with a controlled reduction step, affecting yield and the purity of the resulting aniline intermediate.
- Colour-body impurities — the species responsible for the yellow-brown drift some batches show — can carry through into a finished dye or pigment and dull the target shade.
- Heavy residues concentrate in the still bottoms and reduce the number of passes you get from a crystallisation train, particularly relevant where pharmacopoeial purity is the target.
That chain of consequences is the reason we quote against your written specification rather than a generic "98% technical" grade, and the reason the batch COA is shared for approval before dispatch rather than sent with the invoice.
| Intermediate | Principal outlet |
|---|---|
| 2,3,4-Trichloronitrobenzene CAS 17700-09-3 — this product | Fluoroquinolone intermediates Aclonifen herbicide Dye & pigment synthesis |
| 1,2,3-Trichlorobenzene CAS 87-61-6 | Nitration feedstock for this product Dye carrier / dielectric fluid |
| 2,3,4-Trichloroaniline Downstream reduction product | Quinolone ring construction Azo colourant chemistry |
If your route calls for the precursor, we supply it as well — see 1,2,3-trichlorobenzene. For other nitro-chlorinated isomers, see our full product range and send the CAS number and we will confirm the correct material before quoting.
What actually moves the price of this intermediate
TCNB is not a commodity with a screen price. Knowing what drives the quote helps you time a purchase and read whether an offer is realistic.
Concentrated demand base
With a small number of well-defined outlets — fluoroquinolone synthesis and aclonifen production chief among them — demand is more concentrated and campaign-driven than for a broad commodity intermediate.
- Quote early for campaign tonnage
- Spot buying at peak costs materially more
- Contracted call-off smooths the exposure
Upstream feedstock
The route back to TCNB runs through 1,2,3-trichlorobenzene and the nitration chain. Movements in benzene, chlorine and nitric-acid pricing feed through within a quarter or so.
- Chlorine, benzene and nitric acid set the floor
- Energy cost weighs on nitration and crystallisation
- We flag feedstock-driven moves in the quote
Pharmacopoeial-grade premium
Where a buyer's downstream route feeds an active pharmaceutical ingredient, tighter assay, isomer and heavy-metal limits carry a real cost premium over a general technical grade.
- Confirm which grade your process actually needs
- Pharma-grade documentation adds lead time
- We flag when a lower grade would suffice
Pack format
Cost per kilo falls from 25 kg bags to drums to jumbo bags, though most pharmaceutical intermediate buyers prioritise lot integrity and traceability over the lowest cost pack.
- Drums are the default for pharma-facing buyers
- FIBC suits high-volume agro/dye buyers
- Small packs suit R&D and analytical use
Freight & documentation
Compare quotes on landed cost, not ex-works price — Incoterm, destination and any required dangerous-goods paperwork all move the true delivered cost.
- Compare on landed cost, not ex-works
- Confirm classification before booking freight
- We quote FOB, CIF, CFR or DDP as you prefer
Source availability
A plant turnaround, an environmental inspection or a monsoon disruption can take capacity offline at short notice. Single-sourced buyers on a specialty intermediate feel this hardest.
- We hold a second qualified source on this line
- Qualify the alternate before you need it
- Ask us about dual-source contracts
| If your end use is… | Specify |
|---|---|
| Fluoroquinolone intermediate synthesis | High assay with tight isomer and heavy-metal limits |
| Aclonifen / herbicide route | Standard technical grade, assay-led spec |
| Dye & pigment synthesis | Colour ceiling, low insolubles |
| Custom SNAr chemistry | High assay; confirm isomer distribution |
| Analytical / reference standard | Certified purity, solution or neat, full COA pack |
Not sure which column you are in? Describe the reaction you are running and our technical desk will recommend the grade — including telling you when a cheaper specification would do the job just as well.
Support that goes beyond shipping the drum
What our technical desk will do
- Match a grade to your reaction. Tell us the step you are running and we will recommend the specification — and say so plainly when a tighter, costlier grade would add nothing.
- Be straight about the hazard profile. We state the harmful and irritant classification at enquiry stage so your EHS team can price the controls into the decision, rather than meeting it for the first time on the label.
- Advise on handling and storage for your site conditions — a bagged store in a Gulf summer is a different problem from one in northern Europe, especially for a solid that softens in the low-to-mid 50s °C.
- Review your specification before it goes into a contract, so you are not locked into a limit that no plant can consistently hit.
Regulatory & compliance notes
- Pharmaceutical starting-material traceability. Where this material feeds an active pharmaceutical ingredient, your quality team should confirm the documentation and audit trail your regulatory filing requires before the first delivery.
- Import controls vary by destination. Some jurisdictions apply registration, licensing or end-use declaration requirements to nitro-chlorinated intermediates. We check the destination rules before quoting, not after you have raised the PO.
- Chemical inventory listings differ between regions. Confirm your obligations under the applicable inventory regime for your import volume — we will supply the identity data you need for that filing.
- Agrochemical end-use restrictions can apply to material destined for herbicide manufacture in certain markets. Your regulatory affairs team should confirm the position for your end use.
None of the above is legal advice — your own regulatory affairs team owns the final compliance position for your import and your workplace. What we commit to is giving you accurate product identity data, an honest statement of the hazard classification and complete documentation to work from.
From enquiry to delivered pallet
Send the specification
Product name or CAS 17700-09-3, the assay and impurity limits you work to, quantity, pack preference and destination port.
Receive a firm quote
Pricing, lead time, packing and Incoterm confirmed in writing within 24 hours — our sourcing desk is staffed around the clock.
Qualify and approve
Sample dispatched if you are qualifying a new source. Batch COA shared for your approval before the material is released.
Ship and track
Classification and export documents filed, freight booked, and the consignment tracked through transit and clearance to your plant.
Often bought alongside this grade
Consolidate several intermediates onto one shipment and one invoice. These are the chlorinated aromatics, nitro compounds and precursors our pharmaceutical, agrochemical and dye customers most often order in the same programme. Isomers and related grades we do not yet carry a dedicated page for are listed on our main products page — send us the CAS number and we will confirm availability.
What buyers ask us about 2,3,4-Trichloronitrobenzene
What is this material actually used for?
Is this the same as "1,2,3-trichloro-4-nitrobenzene"?
How is this different from 2,4,6- or 3,4,5-trichloronitrobenzene?
What purity do you normally supply?
What is the minimum order quantity?
How long does delivery take?
The material arrived caked or softened. Is it off-spec?
Why does the solid sometimes appear yellow or yellow-brown rather than white?
Is this a dangerous good? What paperwork comes with it?
- Batch certificate of analysis
- Safety data sheet
- Any required dangerous-goods or shipping declaration
- Commercial invoice, packing list and bill of lading or airway bill
- Certificate of origin and any destination-specific forms
Do you supply to my country?
Do you manufacture this yourself?
Can you hold stock against a production plan?
Request pricing on 2,3,4-Trichloronitrobenzene
Send your required assay, quantity, pack format and destination port. Our sourcing desk is available 24 hours a day, 7 days a week, and comes back with pricing, lead time and packing options — whether that is a single trial sample or a contracted drum programme for the year.