Ortho Toluidine 2-Methylaniline · o-Toluidine · CAS 95-53-4

What is Ortho Toluidine?

Ortho Toluidine (o-Toluidine) is a benzene ring carrying a methyl group at the 2-position and an amine group at the 1-position, formula C₇H₉N. It is supplied as a colourless to pale yellow liquid that turns reddish-brown on exposure to air and light, with a characteristic aromatic amine odour.

Its value as an intermediate comes from the combination of a reactive primary amine with a methyl-substituted ring, which is the structural starting point for a wide range of azo dyes, rubber-vulcanisation accelerators and pharmaceutical actives, most notably local anaesthetics built on the o-toluidide structure.

Commercially it is produced by reducing ortho-nitrotoluene, typically by catalytic hydrogenation or iron/acid reduction at older-generation plants.

Handling follows standard precautions for an aromatic amine with carcinogenic classification — chemical-resistant gloves and eye protection, adequate ventilation, and storage away from strong oxidisers. Like most anilines, it darkens with prolonged exposure to air and light.

Why Ortho Toluidine specifically

• A specific methyl-amine relationship. The ortho (2-) substitution pattern gives reactivity and downstream product properties distinct from meta- and para-toluidine.
• Dye intermediate. A coupling component and diazotisation substrate for azo dyes used on textiles and leather.
• Rubber chemical precursor. A raw material for rubber-vulcanisation accelerators used in tyre and rubber-goods manufacture.
• Pharma building block. The starting material for o-toluidide-based local anaesthetics and other pharmaceutical intermediates.

How Ortho Toluidine is Manufactured

Ortho Toluidine is produced by reducing ortho-nitrotoluene, most commonly by catalytic hydrogenation at modern plants.

• Nitro reduction. ortho-Nitrotoluene is reduced, typically by catalytic hydrogenation under controlled conditions.
• Workup. The crude aniline is separated from catalyst and reaction by-products.
• Purification. The product is purified by distillation to the target assay specification.
• Quality release and packing. Assay, colour and isomer purity are confirmed against specification before the batch is packed and released, typically under nitrogen to limit oxidation.

Typical Commercial Specification

Figures below are representative of commercial-grade Ortho Toluidine. Tell us your downstream route and the grade you need, and we will advise on the specification to order against.

Physical & Chemical Properties

Behaviour in the process

o-Toluidine's reactivity pattern is what dye, rubber and pharma intermediate producers are buying:

• Amine reactivity. The free amine is available for diazotisation, acylation or condensation chemistry.
• Oxidative sensitivity. Like many anilines, it darkens on prolonged exposure to air and light; store accordingly.
• Thermal stability. Stable under normal storage conditions away from strong oxidisers.

Ortho Toluidine and Related Toluidines

Choosing between toluidine isomers comes down to the position of the methyl group relative to the amine that the target synthesis needs.

Stated plainly: a synthesis built around the ortho-methyl pattern needs this specific isomer — the meta- and para-toluidine isomers have different reactivity and are not drop-in substitutes.

Industries We Supply Ortho Toluidine To

The same toluidine isomer feeds a dye-intermediate manufacturer, a rubber-chemical producer and a pharmaceutical intermediate manufacturer. What changes is the downstream functionalisation chemistry and the documentation each requires.

Where Ortho Toluidine is Used

In downstream functionalisation

o-Toluidine's free amine is carried through diazotisation, acylation or condensation chemistry to build the target dye, rubber chemical or pharma intermediate. The ortho-methyl position gives reactivity distinct from the meta- and para-isomers, which is often exactly why a route is designed around this material specifically.

Quality Control & Testing

Every lot is released against a batch-specific Certificate of Analysis, with isomer purity reported alongside the main assay because meta- and para-toluidine carryover affects downstream reaction selectivity.

• o-Toluidine content — by GC assay, the primary grade measure.
• Isomer purity — meta- and para-toluidine carryover, reported because it affects downstream chemistry.
• Colour — reported because oxidation darkens anilines over time.

Common Process Problems & Likely Causes

Packaging, Storage & Shipping

• Standard packing. Drums or jerricans, typically 25 – 200 kg net, with larger bulk formats on contract supply.
• Oxidation protection. Store under nitrogen where possible and keep containers tightly sealed to limit darkening.
• Temperature control. Store in a cool, dry, well-ventilated area away from direct sun, heat and ignition sources.
• Material compatibility. Avoid contact with strong oxidisers.
• Transport classification. Commonly shipped under UN 1708 (Toluidines), Class 6.1, Packing Group II — confirm the correct entry and packing group against your own current SDS before shipping.

Hazards & Safe Handling

Ortho Toluidine is suspected of causing cancer and genetic defects, is toxic if swallowed or absorbed through skin, causes damage to blood and organs through prolonged exposure, and is very toxic to aquatic life. Standard precautions for a regulated aromatic amine and good laboratory and plant practice apply throughout handling.

• Skin and eye contact. Chemical-resistant gloves and goggles are mandatory given the material's dermal absorption hazard; rinse thoroughly with water on contact.
• Inhalation. Use adequate ventilation or local exhaust when handling, given the material's toxicity and classification.
• PPE. Chemical-resistant gloves, safety goggles and, where vapour exposure is a concern, a suitable respirator.
• Environment. Very toxic to aquatic life; avoid uncontrolled release to water and follow local effluent rules.

Regulatory & Compliance Notes

Ortho Toluidine is a registered specialty aromatic amine subject to carcinogen classification in several jurisdictions. Because obligations differ by territory and use, the notes below are orientation rather than legal advice.

• GHS classification. Classified as suspected of causing cancer and genetic defects, toxic if swallowed or in contact with skin, with organ toxicity and aquatic hazards (Signal word: Danger); the SDS carries the full hazard statements for your grade.
• REACH and chemical inventories. Registered under EU REACH and listed on major chemical inventories.
• Carcinogen classification. Classified as a suspected human carcinogen by several regulatory bodies; confirm current exposure-limit and handling requirements for your facility and jurisdiction.
• Dangerous goods transport. Commonly shipped under UN 1708 (Toluidines), Class 6.1, Packing Group II. Confirm the correct entry and packing group with your logistics/EHS team against your current SDS before shipping.
• HS code. Commonly declared under the aromatic amine derivatives heading; confirm the exact tariff line with your customs broker for your jurisdiction.

We Supply Ortho Toluidine Worldwide

Chelora Chemicals is a supplier and export partner, not a single-plant trader. We ship Ortho Toluidine from India and from partner sources to customers across Asia, Europe, the Middle East, Africa, and North and South America, handling the export documentation and freight so the material arrives ready to use.

• Incoterms. EXW, FOB, CIF, CFR and DAP quoted to suit your purchasing terms and freight arrangements.
• Ports. Regular shipments through Nhava Sheva (JNPT) and Mundra, with other ports arranged as routing allows.
• Documentation. Commercial invoice, packing list, certificate of origin, COA and SDS issued as a complete set.
• Flexible volumes. From trial quantities up to repeat bulk shipments on a supply contract.

Buying Ortho Toluidine from Chelora

We are an independent sourcing and supply partner. For this product that means settling three things at enquiry: the purity and isomer-purity grade your application needs, the packing format, and the quantity you are buying.

• Documentation on every lot. Batch-specific COA with assay and isomer breakdown, plus the current SDS.
• Analysis before commitment. Representative analysis shared ahead of a commercial order so your lab can qualify the material.
• Quantities. Trial quantities through to larger bulk shipments on contract supply.
• Inspection. Independent third-party inspection available at loading when the contract requires it.
• Related toluidines. Para Toluidine, Meta Toluidine and related aromatic amine isomers alongside this product from one supplier.

How ordering works

• Send the enquiry. Purity, isomer-purity grade, quantity, destination port and the Incoterm you buy on.
• We quote. Price, lead time, packing format and a sample COA, normally within one working day.
• Qualify the supply. For first orders or dye-grade applications, we share the analysis so your technical team can sign off before you commit.
• Confirm the order. Proforma invoice issued; payment terms agreed against the volume and the relationship.
• Ship and document. Packed, labelled and loaded with the full export document set, and tracked through to arrival.

Related Toluidine Intermediates