Ortho Anisidine
Ortho Anisidine — o-anisidine or 2-methoxyaniline — is the key diazo component behind a large family of high-performance organic azo pigments, prized for the clean reds, oranges and yellows the methoxy-substituted ring gives once coupled. It also has established uses in agrochemical and dye intermediate chemistry.
Chelora Chemicals supplies o-anisidine to pigment manufacturers, dye houses and agrochemical formulators worldwide, in drums, IBCs and tank quantities, with a batch COA and GHS safety data sheet on every consignment.
Product identity
- CAS Number
- 90-04-0
- IUPAC name
- 2-Methoxyaniline
- Molecular formula
- C7H9NO
- Molecular weight
- 123.15 g/mol
- EC / EINECS
- 201-963-1
- UN Number
- 2431
- SMILES
- COc1ccccc1N
- HS Code
- 2922 29*
* Confirm the exact HS heading with your customs broker — classification of amino-ether compounds varies between destination tariffs.
What Ortho Anisidine is used for
Ortho Anisidine is aniline carrying a methoxy group ortho to the amino group. The methoxy substituent is a strong electron donor, which activates the ring and gives a diazonium salt that couples to produce brighter, cleaner, more bathochromic (deeper-shade) azo chromophores than the equivalent chloro- or methyl-substituted anilines. That property has made o-anisidine the diazo component of choice behind several of the industry's best-known high-performance organic pigments — used across automotive paints, plastics and industrial coatings.
In practice o-anisidine is a captive intermediate: plants buy it to diazotise for pigment manufacture, or as a building block in select agrochemical and dye synthesis routes. Very little of it is ever sold on as-is.
Why the isomer and substituent matter
Anisidines are the methoxy analogues of the toluidines, and the substitution pattern changes the chemistry meaningfully:
- 2-Methoxyaniline / ortho anisidine (CAS 90-04-0) — this product. Methoxy ortho to the amine. The dominant anisidine isomer in high-performance pigment manufacture.
- Toluidines — the methyl analogues (ortho, meta and para), used more heavily in rubber-chemical and general dye chemistry. See our toluidine range.
- Chloroanilines — the chloro analogues, used across a parallel but distinct set of azo pigment and antimicrobial chemistry. See our chloroaniline range.
If your purchase order simply says "anisidine", quote us the CAS number and we will confirm the correct material before the order is placed. We supply related chloroanilines, nitroanilines and toluidines across our full product catalogue.
Appearance and handling character
o-Anisidine ships as a colourless to pale yellow or reddish liquid with a melting point just above 6 °C — it can solidify in a genuinely cold winter store or an unheated container, so cold-weather logistics deserve a moment's thought. It is only slightly soluble in water and miscible with most organic solvents. Like other primary aromatic amines it darkens on prolonged exposure to air and light. Read the safety section before planning any handling programme: this material is toxic by all three exposure routes and carries a possible-carcinogen classification.
| Parameter | Typical value |
|---|---|
| Appearance | Colourless to pale yellow/red liquid |
| Assay (GC) | 99.0% min |
| Water content (KF) | 0.3% max |
| Colour (APHA) | 100 max |
| Isomeric & related impurities | 1.0% max |
| Specific gravity | Reported per batch |
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 pigment process demands a tighter colour ceiling or a specific impurity limit, send us the specification and we will quote against it rather than against a generic grade.
| Property | Value |
|---|---|
| Physical state | Liquid at ambient (solidifies below ≈ 6 °C) |
| Melting point | ≈ 6.2 °C |
| Boiling point | ≈ 224 °C @ 760 mmHg |
| Flash point | ≈ 118 °C (open cup) |
| Relative density | ≈ 1.092 (20 °C) |
| Water solubility | Slightly soluble |
| Organic solubility | Miscible with alcohols, ethers & most organic solvents |
| Odour | Amine-like, mild aromatic |
Physical constants compiled from public reference data for CAS 90-04-0 and rounded for readability. Treat them as orientation, not as a specification.
Where our customers put this molecule to work
o-Anisidine's dominant outlet is high-performance organic pigment manufacture, with established secondary demand from agrochemical and dye producers.
High-performance organic pigments
The defining outlet. Diazotised o-anisidine couples onto naphthol AS derivatives to build some of the industry's best-known high-performance red and orange pigments, prized in automotive paint, plastics and industrial coatings for brightness and fastness.
- Diazo component for naphthol AS pigments
- Shade and fastness depend directly on purity
- See our full aniline intermediate range
Agrochemical intermediates
The 2-methoxyphenylamine fragment is used in the synthesis of select fungicide and herbicide actives, where the ortho-methoxy pattern is part of the target molecule's structure.
- Substituted amide and urea chemistry
- Custom agrochemical intermediate synthesis
- See our agrochemical intermediate range
Dye intermediate chemistry
o-Anisidine and its derivatives serve as building blocks in select disperse and azo dye synthesis routes, where the electron-rich methoxy-substituted ring is used to tune the shade and fastness of the finished dye.
- Diazo component in specialty dye chemistry
- Complementary to toluidine-based routes
- See also para toluidine
Pharmaceutical & fine chemical intermediates
The 2-methoxyphenyl fragment appears in several pharmaceutical and specialty chemical synthesis routes, installed through amide formation, ring construction or N-arylation.
- Amide, urea and sulfonamide formation
- Heterocyclic ring construction
- See also ortho toluidine
Fine & specialty synthesis
A well-characterised amino-ether building block for custom amides, azo dyes, Schiff bases and ligand work where the electron-rich ortho-methoxyaniline pattern is specifically required.
- Custom amide and azo dye formation
- Ligand and coordination chemistry
- Available in trial and laboratory quantities
Contract & scheduled supply
Pigment plants run to campaign, not to a calendar month. Most o-anisidine buyers want tonnage released against a production plan rather than in one shipment. We hold inventory and release it to your schedule.
- Annual contracts with scheduled call-off
- Price held across the contract period
- Second source held in reserve
How we supply Ortho Anisidine
Chelora Chemicals is a supplier and sourcing partner, not a manufacturer. We own no anisidine plant — and for a specification-sensitive, colour-critical 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 colour ceiling, your price point and your delivery window.
We keep a second qualified source on this line. When a plant goes down for maintenance, your campaign switches source rather than stalling.
- Specification read against the CAS first. We confirm you need 90-04-0 and not a toluidine or a different anisidine isomer before we quote a price.
- Batch COA shared before dispatch. You approve the assay, colour and impurity profile against your own spec while the material is still in our warehouse.
- Hazard status stated up front. This material is toxic by all three exposure routes and carries a possible-carcinogen classification, and 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 or pigment lab runs a coupling trial before the full quantity ever moves.
- Cold-weather packing planned. With a melting point just above 6 °C, we flag cold-climate routings and pack accordingly so the material does not arrive partly solidified in an unheated container.
- 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 o-anisidine alongside other intermediates from our range — one invoice, one shipment, one counterparty.
Packed the way your plant receives it
As a liquid amine with a near-ambient melting point, o-anisidine is packed and routed with both handling and cold-weather stability in mind. Tell us how it will be charged at your end and we will quote the format that suits your operation.
UN-approved steel or HDPE drums
The standard format for LCL shipments and for plants charging drum-wise. Nitrogen-blanketed on request to limit oxidative colour drift.
IBC totes
Composite or steel IBCs for mid-volume buyers with mechanical unloading. Fewer handling movements per tonne than drums and a lower packing cost.
ISO tank containers
Bulk liquid movement for high-volume buyers running continuous consumption. The lowest landed cost per kilo at container scale.
Samples & trial packs
Laboratory samples and pilot quantities in sealed glass or lined-steel containers, dispatched by courier so your pigment lab can run a coupling trial first.
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
Pigment 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 possible carcinogen
This is the point on the page that matters most. Ortho anisidine is toxic by ingestion, skin contact and inhalation, carries a suspected-mutagenicity entry, and is classified by IARC in Group 2B, "possibly carcinogenic to humans." 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
H350May cause cancer.H341Suspected of causing genetic defects.H301Toxic if swallowed.H311Toxic in contact with skin.H331Toxic if inhaled.
Hazard statements reflect the harmonised GHS classification commonly published for CAS 90-04-0 (GHS06 Toxic, GHS08 Health hazard). IARC classifies o-anisidine in Group 2B — possibly carcinogenic to humans. Supplier classifications may differ in detail; always read the SDS issued with your specific batch, and treat the carcinogenicity and mutagenicity entries as the ones that shape your controls.
Spill & emergency orientation
Plan your response before the drum arrives, not after a valve leaks. 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.
- Contain, do not hose to drain. Bund and collect spilled liquid into a labelled container; never wash it to a drain or watercourse.
- Assume skin absorption. Contaminated clothing is a continuing exposure route — remove it immediately and wash the skin thoroughly.
- Have the SDS with the casualty. Substituted anilines can cause methaemoglobinaemia, and the treating clinician needs the product identity and CAS number in hand.
- Watch for cold-weather solidification. Below roughly 6 °C the material can partially solidify in a drum or line — plan gentle, controlled warming rather than forcing frozen product through a pump.
- Record the exposure. For a possible carcinogen with a mutagenicity flag, many occupational regimes expect an exposure record to be created and retained. That is a decision for your EHS function, and it is easier made before an incident than after one.
Storage
- Cool but frost-free store, away from direct sunlight and heat sources. The melting point sits just above 6 °C, so genuinely cold storage or transit can cause partial solidification — plan warming capability rather than an unheated cold store.
- Keep containers tightly closed. Air and light drive the colour drift typical of anilines, and an open drum also picks up moisture.
- Segregate from oxidising agents, strong acids and acid chlorides. As a primary aromatic amine it reacts exothermically with acylating and oxidising reagents.
- Access-controlled storage. For a possible carcinogen, restricting who can reach the store is part of the control, not an administrative nicety.
- Shelf life is typically 12–24 months in sealed original packing under these conditions. Re-assay before use after long storage.
Handling & PPE
- Design exposure out, do not manage it down. Closed transfer and pump-fed charging first, local exhaust ventilation second, PPE last.
- Skin protection is the priority. Substituted anilines are absorbed through intact skin — chemical-resistant gloves and coveralls, not just splash protection.
- Respiratory protection where vapour concentrations may build — particularly in enclosed transfer areas — per your own exposure assessment.
- Health surveillance where indicated. The combined carcinogenicity and mutagenicity flags mean some sites build periodic monitoring into their occupational health programme for regular handlers.
- Never discharge to drain or watercourse. Collect spills and dispose of them as regulated chemical waste.
Transport
o-Anisidine moves as regulated cargo under UN 2431. We classify each consignment, apply UN-approved packaging and labelling, and file the dangerous-goods declaration before the booking is made. The applicable class and packing group are stated on your shipping documents and SDS — ask us for the current DG 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.
Certificate of Analysis
Batch-specific assay by GC, water content by Karl Fischer, colour (APHA), appearance and impurity profile — checked against your purchase specification before we release the goods.
GHS Safety Data Sheet
Full 16-section SDS in GHS format covering hazards, exposure controls, handling, storage, spill response, toxicology and disposal — issued in the language your destination requires.
Dangerous Goods Declaration
UN 2431, hazard class, packing group and IMDG or IATA declaration prepared and filed before the container is booked, with correctly marked and labelled packaging.
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 pigment lab qualifies is exactly what arrives. Retention samples held against the batch.
Why the methoxy group changes the shade
Almost everything made from o-anisidine leaves through diazotisation. The methoxy group's electron-donating character is what makes the difference downstream. The routes below are the general industrial pattern, not a process disclosure.
Start with the amino-ether
o-Anisidine provides a primary aromatic amine with an electron-donating methoxy group ortho to the nitrogen, giving a more reactive, electron-rich ring than a toluidine or chloroaniline.
Diazotise
Sodium nitrite in acid at low temperature gives the diazonium salt — a step that needs careful temperature control given the electron-rich, more reactive ring.
Couple for shade
The diazonium salt is coupled onto a naphthol AS component, and the methoxy substituent gives a deeper, more bathochromic shade than the equivalent methyl- or chloro-substituted coupling.
Finish to grade
The crude pigment is filtered, washed and finished — particle size, crystal form and surface treatment are tuned to the application, whether automotive, plastics or industrial coatings.
Why feed quality carries through the whole route
The whole value of this route lies in shade and fastness, so anything in the feed that competes for the diazotisation chemistry, or carries its own colour, follows the material into the finished pigment:
- Isomeric anisidines and toluidines diazotise in parallel and give structurally similar but off-shade chromophores — a real problem in colour-critical pigment work.
- Residual water can complicate diazotisation control at the low temperatures this reaction typically runs at.
- Oxidation products — the coloured species responsible for amber drift in storage — dull a finished shade directly, since the whole point of the feed is its own eventual colour.
- Heavy residues concentrate in mother liquors and can affect particle size and crystal habit in the finished pigment.
That chain of consequences is the reason we quote against your written specification rather than a generic "99% technical" grade, and the reason the batch COA is shared for approval before dispatch rather than sent with the invoice.
| Diazo component | Typical shade character |
|---|---|
| Ortho Anisidine CAS 90-04-0 — this product | Deep, bright reds & oranges High-performance pigment grade |
| Para Toluidine CAS 106-49-0 | Cleaner, lighter reds General azo pigment chemistry |
| Para Chloroaniline CAS 106-47-8 | Deeper shades, solvent-resistant General azo pigment chemistry |
If your route calls for a different diazo component, we supply those as well — see our full product catalogue. Send the CAS number and we will confirm the correct material before quoting.
What actually moves the price of this intermediate
o-Anisidine 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.
Pigment demand cycles
Automotive paint, industrial coatings and plastics colourant demand pull on the same intermediate through the year, tracking those end industries' own production cycles.
- Quote early for campaign tonnage
- Spot buying at peak costs materially more
- Contracted call-off smooths the exposure
Upstream feedstock
The route back to o-anisidine runs through nitroanisole and selective reduction. Movements in benzene, methanol and catalyst metals feed through to the aniline within a quarter or so.
- Benzene and methanol prices set the floor
- Catalyst and energy costs weigh on the reduction step
- We flag feedstock-driven moves in the quote
Regulatory pressure
The possible-carcinogen and mutagenicity classifications raise the compliance cost of producing, storing and moving this material. That cost sits inside the price.
- Handling obligations vary by jurisdiction
- Some markets restrict certain end uses
- We check destination rules before quoting
Pack format
Cost per kilo falls from drums to IBCs to ISO tanks. Tank movement is worthwhile only above a certain volume threshold — we will tell you honestly where that threshold sits for your quantity.
- Drums suit trial and mid-size orders
- ISO tanks are cheapest per kilo at scale
- We size the format to your consumption rate
Freight & DG surcharges
This is regulated cargo, so ocean freight carries a hazardous surcharge and space is tighter than for general cargo. Destination and Incoterm move landed cost as much as the ex-works price does.
- Compare on landed cost, not ex-works
- DG space books out ahead of peak season
- We quote FOB, CIF, CFR or DDP as you prefer
Source availability
A plant turnaround or an environmental inspection can take capacity offline at short notice on this line. Single-sourced buyers 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 |
|---|---|
| High-performance pigments | Tight colour ceiling, very low isomer content |
| Agrochemical synthesis | High assay, tight moisture control |
| Specialty dye chemistry | Colour ceiling, controlled impurity profile |
| Pharmaceutical chain | Tight isomer limit; metals and residues reported |
| Laboratory / R&D | Small pack, high purity, full analytical pack |
Not sure which column you are in? Describe the coupling or 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 coupling or reaction 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 possible-carcinogen and mutagenicity classifications 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 — cold-weather stability and closed-transfer design look different in different plant layouts.
- Review your specification before it goes into a contract, so you are not locked into a colour limit that no plant can consistently hit.
Regulatory & compliance notes
- Possible-carcinogen obligations are jurisdiction-specific. Several regimes impose exposure limits, health surveillance and record retention for chemicals with this hazard profile. Confirm what applies at your site before the first delivery.
- Import controls vary by destination. Some jurisdictions apply registration, licensing or end-use declaration requirements to this material. 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.
- Downstream article restrictions can apply to certain colourant and consumer applications. Your regulatory team should confirm the finished-article position for the end use you have in mind.
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 drum
Send the specification
Product name or CAS 90-04-0, the assay and colour 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
DG classification filed, freight booked, export documents issued, 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 anilines and aromatics our pigment, agrochemical and fine chemical customers most often order in the same programme. Each of the following is part of our wider aniline intermediate range — browse the full product catalogue for current availability and specification sheets.
What buyers ask us about Ortho Anisidine
Is this material a classified carcinogen?
Can I use a toluidine or chloroaniline instead?
What purity do you normally supply?
What is the minimum order quantity?
How long does delivery take?
The drum arrived partly solidified. Is it off-spec?
How should we store it, and what is the shelf life?
Is this a dangerous good? What paperwork comes with it?
- Batch certificate of analysis
- GHS-format safety data sheet
- Dangerous-goods declaration with UN number, class and packing group
- 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 Ortho Anisidine
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 drum or a contracted tank programme for the year.