3-Chloro-o-toluidine
A high-purity chlorinated toluidine supplied for azo dye and pigment manufacture, agrochemical intermediates, and specialty synthesis.
What is 3-Chloro-o-toluidine?
3-Chloro-o-toluidine — 3COT, or 3-chloro-2-methylaniline — is a colourless to amber liquid carrying a methyl group next to the amino group and a chlorine on the far side of it.
The methyl and chlorine pull in opposite electronic directions: one donates electron density and one withdraws it. The result is an amine with a shade and coupling behaviour distinct from either the plain toluidines or the plain chloroanilines, which is precisely why colour chemists specify it.
At Chelora Chemicals, 3COT is distilled to a controlled isomer profile and low colour, with moisture held to specification, giving dye and pigment manufacturers reproducible diazotisation between batches.
- Appearance
- Colourless to amber liquid
- Odour
- Characteristic amine odour
- Solubility
- Slightly soluble in water; soluble in alcohol, ether, dilute acid
- Function
- Chemical intermediate
- Grade
- Technical / dye
Formula diagram
Toluidine ring with chlorine at the 3-position
- Molecular formulaC7H8ClN
- Molecular weight141.60 g/mol
- IUPAC name3-Chloro-2-methylaniline
- Functional groupsPrimary aromatic amine, aryl chloride, alkyl
- CAS number87-60-5
Technical product information
Standard specification for Chelora Chemicals' technical grade 3-Chloro-o-toluidine. Custom-grade and bulk specifications are available on request.
| Chemical name | 3-Chloro-o-toluidine |
|---|---|
| Synonyms | 3COT, 3-Chloro-2-methylaniline, 3-Chloro-2-toluidine |
| CAS number | 87-60-5 |
| Molecular formula | C7H8ClN |
| Molecular weight | 141.60 g/mol |
| Assay (purity) | ≥ 99.0% |
| Appearance | Clear, colourless to amber liquid |
| Density (20°C) | 1.15–1.18 g/cm³ |
| Boiling point | approx. 240°C |
| Flash point | > 110°C (closed cup) |
| Isomer content | ≤ 0.5% |
| Water content | ≤ 0.3% |
| Packaging | 200 kg drums, 1000 kg IBC |
| Shelf life | 12 months in sealed original packaging |
Applications of 3-Chloro-o-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 and red pigment manufacture.
Agrochemical intermediates
Converted into amide and urea derivatives used in crop-protection synthesis.
Pharmaceutical intermediates
Provides a substituted toluidine core for amide and heterocyclic building blocks.
Rubber chemicals
Applied in amine-based antioxidant and accelerator synthesis.
Specialty chemicals
Used in optical brightener and specialty amine derivative manufacture.
Why choose Chelora Chemicals
Every batch of 3-Chloro-o-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% 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 quantities, with samples on request.
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 — chlorinated toluidines darken on oxidation.
- 04Segregate from strong oxidising agents, acids, and acid chlorides.
- 05Use compatible containers: lined steel, stainless steel, or HDPE.
- 06Prevent any release to drains, surface water, or soil.
Handling precautions
3COT is toxic by inhalation, ingestion, and skin absorption. It is for industrial use by trained personnel only.
Chlorinated aromatic amines are readily absorbed through intact skin and cause methaemoglobin formation. Chemical-resistant gloves, coveralls, and eye protection are required.
Use closed transfer and local exhaust ventilation for decanting, charging, and heated operations.
Prevent release to the environment; the product is toxic to aquatic life.
Refer to the full Safety Data Sheet for exposure limits, medical surveillance, spill response, and first-aid measures before use.
Frequently asked questions
What is 3-Chloro-o-toluidine used for?
It is an intermediate for azo dyes and pigments, agrochemical actives, and pharmaceutical building blocks. It is not used as a finished product.
How does it differ from 5-chloro-2-methylaniline?
Both are C7H8ClN with a weight of 141.60 and both carry a methyl next to the amino group. They differ in where the chlorine sits, which changes shade, coupling behaviour, and melting point — 3COT is a liquid, the 5-chloro isomer a low-melting solid.
Why combine a methyl and a chlorine on one ring?
The methyl donates electron density and the chlorine withdraws it. That push-pull arrangement produces colour and fastness characteristics that neither a plain toluidine nor a plain chloroaniline can give.
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.
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.
What purity do you supply?
Standard technical grade is supplied at a minimum assay of 99% with isomer content at or below 0.5% and water at or below 0.3%. Tighter specifications can be produced to order.
What packaging sizes are available?
200 kg drums and 1000 kg IBCs, with samples available for shade and coupling trials.
How long can it be stored?
12 months from manufacture in sealed original packaging under the recommended conditions. Colour will develop over time even when assay holds.
Is 3COT hazardous?
Yes. It is toxic by several routes, readily absorbed through skin, and toxic to aquatic life. Full engineering controls and PPE are required per the Safety Data Sheet.
Why is skin absorption emphasised?
Chlorinated aromatic amines pass through intact skin efficiently, so a splash that is not washed off immediately can produce a systemic dose without any inhalation exposure.
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.