Ortho Toluidine
A high-purity methylated aromatic amine supplied for azo dye and pigment manufacture, rubber chemical synthesis, and specialty intermediates.
What is Ortho Toluidine?
Ortho Toluidine — OT, or 2-methylaniline — is a colourless to pale yellow liquid with a methyl group on the carbon next to the amino group. It darkens to reddish-brown on exposure to air and light.
The ortho methyl group both donates electron density to the ring and partially shields the nitrogen, giving coupling behaviour and shades distinct from aniline or the para isomer. It is one of the three toluidines separated from the mixture produced by reducing nitrotoluene.
At Chelora Chemicals, OT is distilled to a controlled isomer profile and low colour. Because the substance carries a strict carcinogen classification, it is supplied only to industrial users with the containment and health surveillance that classification requires.
- Appearance
- Colourless to pale yellow liquid
- Odour
- Characteristic amine odour
- Solubility
- Slightly soluble in water; soluble in alcohol, ether, dilute acid
- Function
- Chemical intermediate
- Grade
- Technical / dye
Formula diagram
Aniline ring with a methyl group in the ortho position
- Molecular formulaC7H9N
- Molecular weight107.15 g/mol
- IUPAC name2-Methylaniline
- Functional groupsPrimary aromatic amine, alkyl
- CAS number95-53-4
Technical product information
Standard specification for Chelora Chemicals' technical grade Ortho Toluidine. Custom-grade and bulk specifications are available on request.
| Chemical name | Ortho Toluidine |
|---|---|
| Synonyms | OT, 2-Methylaniline, o-Toluidine, 2-Aminotoluene |
| CAS number | 95-53-4 |
| Molecular formula | C7H9N |
| Molecular weight | 107.15 g/mol |
| Assay (purity) | ≥ 99.5% |
| Appearance | Clear, colourless to pale yellow liquid |
| Density (20°C) | 0.998–1.008 g/cm³ |
| Boiling point | 200–202°C |
| Melting point | −16°C |
| Flash point | 85°C (closed cup) |
| Isomer content | ≤ 0.3% |
| Water content | ≤ 0.2% |
| Packaging | 200 kg drums, 1000 kg IBC, ISO tank |
| Shelf life | 12 months in sealed original packaging |
Applications of Ortho Toluidine
Azo dyes
Diazotised as a colour base for azo dyes across textile and leather applications.
Organic pigments
Used as a diazo component in yellow, orange, and red pigment manufacture.
Rubber chemicals
Feeds the synthesis of accelerators, antioxidants, and antidegradants.
Agrochemical intermediates
Applied in crop-protection routes built on substituted toluidine cores.
Pharmaceutical intermediates
Provides a methylated aniline core for amide and heterocyclic building blocks.
Specialty chemicals
Used in optical brightener and specialty amine derivative manufacture.
Why choose Chelora Chemicals
Every batch of Ortho Toluidine is manufactured, tested, and documented to a standard that formulators and process chemists can build on with confidence — from first sample to full production volume.
Consistent purity
Assay controlled at ≥99.5% with isomer content, colour, and water verified before dispatch.
Full documentation
COA, SDS, and regulatory data supplied with every shipment.
Flexible volumes
From 200 kg drums to IBC and ISO tank quantities.
Technical support
Process, handling, and compliance guidance from our chemistry team.
Storage and guidelines
- 01Store in tightly sealed original containers under a dry, inert atmosphere where possible.
- 02Keep in a cool, dry, well-ventilated store away from direct sunlight and heat.
- 03Protect from air and light — toluidines darken quickly on oxidation.
- 04Segregate from strong oxidising agents, acids, and acid chlorides.
- 05Use compatible containers: lined steel, stainless steel, or HDPE.
- 06Store in a locked or access-controlled area with clear carcinogen warning signage.
Handling precautions
Ortho toluidine is classified as a carcinogen and is toxic by inhalation, ingestion, and skin absorption. It is for industrial use by trained personnel only.
The carcinogen classification means exposure must be reduced to the lowest technically achievable level rather than merely kept below a limit. Closed handling, exposure monitoring, exposure records, and health surveillance may be legally required at your site.
The substance is readily absorbed through intact skin, and skin absorption can be the dominant exposure route even where air monitoring shows low levels. Glove selection with verified breakthrough data and prompt decontamination matter more here than for most products in this range.
Absorbed material also forms methaemoglobin, reducing the blood's oxygen-carrying capacity.
Use closed transfer and local exhaust ventilation for decanting, charging, and heated operations, and prevent release to drains, surface water, and soil.
Refer to the full Safety Data Sheet for exposure limits, health surveillance, spill response, and first-aid measures before use.
Frequently asked questions
What is Ortho Toluidine used for?
It is an intermediate for azo dyes and pigments, rubber chemicals, agrochemicals, and pharmaceutical building blocks. It is not used as a finished product.
What is the difference between ortho, meta, and para toluidine?
All three are C7H9N with a weight of 107.15 and differ only in where the methyl group sits relative to the amino group. Ortho and meta are liquids at room temperature and para is a solid melting near 44°C. They give different shades and are not interchangeable.
How is OT manufactured?
By reducing ortho nitrotoluene, which is itself separated from the mixture produced when toluene is nitrated. Isomer purity of the nitrotoluene feed carries through to the finished amine.
Is ortho toluidine a carcinogen?
It carries a strict carcinogen classification and is treated as a recognised human carcinogen by major health authorities, with bladder cancer the principal concern in occupational studies. Exposure must be reduced to the lowest technically achievable level and health surveillance may be mandatory.
Why is skin absorption emphasised for this product?
It passes through intact skin efficiently, so a splash that is not washed off immediately can deliver a systemic dose even where air monitoring shows nothing. This is why glove breakthrough data and decontamination procedures matter as much as ventilation.
Why does the liquid darken during storage?
Aromatic amines oxidise on contact with air and light. Assay is generally unaffected, but colour matters for shade-critical work, so nitrogen-blanketed, cool, dark storage is worthwhile.
Is it soluble in water?
Only slightly in neutral water. It dissolves readily in alcohols, ether, and dilute mineral acid, and acid dissolution is the usual first step before diazotisation.
What purity do you supply?
Standard technical grade is supplied at a minimum assay of 99.5% with isomer content at or below 0.3% and water at or below 0.2%. Tighter specifications can be produced to order.
What packaging sizes are available?
200 kg drums, 1000 kg IBCs, and ISO tanks. Supply is subject to confirmation of the receiving site's handling capability and regulatory position.
Are there regulatory restrictions on azo colourants made from toluidines?
Several jurisdictions restrict azo dyes that can release certain aromatic amines in consumer textiles and leather, and ortho toluidine is among the amines commonly listed. Check your finished-article market before committing to a route using this base.
Do you provide a Certificate of Analysis?
Yes. Every batch is dispatched with a Certificate of Analysis and Safety Data Sheet covering assay, isomer content, density, colour, water content, and appearance.