Agro, pharma & specialty intermediate
Ortho Phenylene Diamine (OPD) Supplier & Distributor in India & Worldwide
Chelora Agrochem is a trusted Ortho Phenylene Diamine (OPD) supplier and distributor in India, connecting buyers with high-purity material sourced from leading, quality-approved manufacturers. Our o-phenylenediamine meets 99% min purity with controlled isomer content and colour, full documentation and reliable bulk supply across India and to buyers worldwide.
As a specialised distributor of chemical products, we do not manufacture in-house — instead we source only from reliable, audited manufacturers, giving you dependable material, competitive pricing and a single point of contact for all your OPD requirements, backed by COA, MSDS and TDS on every order.
- CAS number
- 95-54-5
- Formula
- C6H8N2
- Molecular weight
- 108.14 g/mol
- Purity
- 99% min
Quick product specifications
Ortho Phenylene Diamine at a glance
Identifiers, physical data and trade codes for OPD. Batch-specific figures are confirmed on the Certificate of Analysis supplied with each consignment, in India and on export shipments alike.
- Chemical name
- o-Phenylenediamine
- CAS number
- 95-54-5
- EC number
- 202-430-6
- Molecular formula
- C6H8N2
- Molecular weight
- 108.14 g/mol
- IUPAC name
- Benzene-1,2-diamine
- HS code
- 2921 51 10
- UN number
- UN 1673Phenylenediamines — class 6.1, PG III
- Appearance
- White to light-brown flakes or crystalsDarkens to brown on exposure to air and light
- Melting point
- 100–103 °C
- Boiling point
- 256–258 °C
- Solubility
- Slightly soluble in cold waterMore soluble in hot water; soluble in ethanol, ether and chloroform
- Purity
- 99% min
- Moisture
- 0.5% max
- Synonyms
- OPD1,2-Diaminobenzene · o-Diaminobenzene · 1,2-Benzenediamine
- Product form
- Flakes — lined drums, nitrogen-flushed
- Documentation
- COA, MSDS & TDSSupplied with every order
Product overview
What is Ortho Phenylene Diamine?
Ortho Phenylene Diamine (o-phenylenediamine, OPD) is an aromatic diamine whose two neighbouring amino groups close readily into five- and six-membered rings. That makes it the standard precursor for benzimidazoles — including the fungicides carbendazim, benomyl, thiophanate-methyl and thiabendazole — as well as benzotriazole, 2-mercaptobenzimidazole and quinoxalines.
With the formula C6H8N2 (CAS 95-54-5), OPD is a white to light-brown crystalline solid melting at about 102 °C. It oxidises in air and light — fresh material is almost white, aged material turns brown — so colour is a practical measure of quality. Industrially it is made by reducing Ortho Nitro Aniline.
Because both amines sit side by side, OPD condenses with acids, aldehydes, carbamates and 1,2-dicarbonyls in a single step — which is why fungicide, API and corrosion-inhibitor producers specify it closely by assay, colour and meta / para isomer content.
How it is made
2-Nitrochlorobenzene is reacted with ammonia to give 2-nitroaniline, and the nitro group is then reduced — by catalytic hydrogenation or sulphide reduction — to o-phenylenediamine, which is purified and flaked under nitrogen.
What that means for your process
- Two adjacent amino groups for one-step ring closure
- Clean route to benzimidazole, benzotriazole and quinoxaline cores
- Meta / para isomers and colour controlled to grade
- Nitrogen-flushed packing to slow oxidation in storage
Applications
What is Ortho Phenylene Diamine used for?
OPD is used as an intermediate in the synthesis of fungicides, pharmaceuticals, corrosion inhibitors, rubber chemicals and pigments. Its main applications, industry by industry, include:
Agrochemicals
The largest use. OPD builds the benzimidazole core of a whole family of systemic fungicides.
- Carbendazim and benomyl
- Thiophanate-methyl
- Thiabendazole and fuberidazole
Pharmaceuticals
A standard entry point for benzimidazole and related nitrogen heterocycles.
- Benzimidazole, benzimidazolone and quinoxaline scaffolds
- Intermediates for API and custom synthesis
- Analytical reagent — chromogenic peroxidase substrate
Industrial & specialty
Condensed into additives that protect metals and rubber, and into pigment intermediates.
- Benzotriazole — corrosion inhibitor for copper and its alloys
- 2-Mercaptobenzimidazole — rubber antioxidant
- Benzimidazolone pigment intermediates
Process route
How is Ortho Phenylene Diamine used downstream?
OPD enters a synthesis as the diamine. One amine condenses with a carbonyl, carbamate or nitrite partner, the second closes the ring, and the resulting benzimidazole or triazole core is finished into the product — the ortho geometry is exactly why it is chosen over the meta and para isomers.
Ortho Phenylene Diamine
Charged as the diamine. Assay and colour decide downstream purity.
C6H8N2Condensation
One amine reacts with a carbamate, acid, aldehyde, urea or nitrite partner.
Carbonyl / carbamate partnerRing closure
The second amine closes the ring to a benzimidazole, benzotriazole or quinoxaline.
Heterocyclic coreFinished product
Purified into the fungicide, API, inhibitor or pigment intermediate.
Active or additiveIn depth
Ortho Phenylene Diamine applications by industry
Below is a detailed breakdown of where OPD is used and the role it plays in each downstream product.
| Industry | Typical downstream products | Role of OPD |
|---|---|---|
| Agrochemicals | Carbendazim, benomyl | Benzimidazole core |
| Agrochemicals | Thiophanate-methyl | Core diamine |
| Agrochemicals | Thiabendazole, fuberidazole | Benzimidazole core |
| Pharmaceuticals | Benzimidazole and quinoxaline APIs | Building block |
| Industrial | Benzotriazole (corrosion inhibitor) | Cyclised with nitrous acid |
| Rubber chemicals | 2-Mercaptobenzimidazole (antioxidant) | Condensed with xanthate |
| Pigments | Benzimidazolone pigment intermediates | Via 2-benzimidazolone |
Safety
Is Ortho Phenylene Diamine hazardous?
Yes. o-Phenylenediamine is toxic if swallowed, harmful in contact with skin or if inhaled, causes serious eye irritation, may cause an allergic skin reaction, is suspected of causing genetic defects and cancer, and is very toxic to aquatic life with long-lasting effects. With correct PPE, dust control and containment it is safely handled in industry.
OPD should be stored in tightly sealed containers in a cool, dry, dark and well-ventilated place away from oxidisers, acids, acid chlorides and anhydrides. It oxidises and darkens in air and light, so nitrogen-flushed packs and prompt resealing are recommended. Prevent release to drains and waterways. A full MSDS is supplied with every order.
Signal word: Danger
Toxic if swallowed · skin sensitiser · suspected mutagen and carcinogen · very toxic to aquatic life
Safe-handling essentials
- Chemical-resistant gloves, goggles and protective clothing — avoid all skin contact
- Handle flakes with dust control and local exhaust; wear a particulate respirator where dust forms
- Keep containers tightly sealed, cool and out of direct light
- Reseal under nitrogen after opening to limit oxidation and colour gain
- Store away from oxidisers, acids and acid chlorides
- Never allow release to drains, soil or waterways
- Transport as UN 1673 — a regulated dangerous good
Grades
Ortho Phenylene Diamine grades & technical specifications
We supply OPD in technical and high-purity grades to match agrochemical, pharmaceutical and specialty-chemical requirements.
| Parameter | Specification |
|---|---|
| Assay (purity) | 99% min — higher-purity grades on request |
| Appearance | White to light-brown flakes |
| Melting point | 100–103 °C |
| m- and p-Phenylenediamine | As per grade |
| o-Nitroaniline (residual) | As per grade |
| Moisture | 0.5% max |
| Colour | As per grade |
| Product form | Flakes — lined drums, nitrogen-flushed |
Note: Values are representative. Batch-specific figures are provided on the Certificate of Analysis (COA) supplied with each consignment.
Supply
Packaging, MOQ & supply
From trial quantities for process validation to repeat container loads on contract — packed, documented and dispatched to your plant in India or overseas.
Packaging
25 kg or 50 kg fibre or HDPE drums with inner liner, nitrogen-flushed to protect colour.
Minimum order quantity
Flexible — single drums for trials through to full-container loads.
Shelf life
Good shelf life in sealed, unopened drums stored cool, dry and dark; colour is the first sign of ageing.
Dispatch
Pan-India dispatch and worldwide export with complete documentation and logistics support.
Why buy from us
Why choose Chelora as your OPD supplier?
As an established Ortho Phenylene Diamine supplier and distributor based in India and shipping worldwide, we work with a wide network of trusted manufacturers to combine consistent quality with dependable service. More about Chelora Agrochem.
High purity, every batch
99% min assay, sourced only from quality-approved manufacturers we have worked with and audited.
Full documentation
COA, MSDS and TDS travel with every order, so your QA and EHS teams are never chasing paperwork.
Reliable bulk supply, flexible MOQ
Trial packs for process work through to repeat container loads on schedule.
Worldwide supply
Export-grade packing, documentation and on-time dispatch to plants across Asia, the Middle East, Europe, Africa and the Americas.
Technical & safe-handling support
Guidance on storage, nitrogen flushing, dust control, PPE and process fit from a team that knows aromatic amines.
One point of contact
Source OPD alongside your other intermediates — one enquiry, one team, one invoice.
Ordering
How to order Ortho Phenylene Diamine from Chelora
Ordering is simple and fast — most enquiries are answered with pricing and availability within 24 hours.
- 1
Send your enquiry
Tell us the grade, quantity and application you are buying for.
- 2
Receive a quotation
We send pricing along with the COA and MSDS for your review.
- 3
Request a sample
Test suitability for your process before you commit to a bulk order.
- 4
Confirm the order
Lock in quantity, packaging and delivery preference.
- 5
Dispatch & tracking
We dispatch with full documentation and keep you updated until delivery.
Documentation
Ortho Phenylene Diamine MSDS & COA
A summary of key safety information and a representative Certificate of Analysis. The complete 16-section Safety Data Sheet and the actual batch COA are supplied with each shipment — and both are sent with your quotation when you ask for a quote.
Safety data summary (MSDS)
| Section | Details |
|---|---|
| Hazard classification | Toxic if swallowed; harmful by skin contact and inhalation; eye irritant; skin sensitiser; suspected mutagen and carcinogen; very toxic to aquatic life |
| Signal word | Danger |
| First aid — inhalation | Move to fresh air; seek medical help |
| First aid — skin | Remove contaminated clothing; wash with soap & plenty of water |
| First aid — eyes | Rinse with water for at least 15 minutes; get medical advice |
| First aid — ingestion | Rinse mouth; call a doctor immediately |
| Handling | Use PPE; avoid dust; ventilate |
| Storage | Cool, dry, dark, sealed, ideally under nitrogen; away from oxidisers |
| Decomposition | Emits nitrogen oxides and carbon oxides on burning |
| Environment | Prevent release to drains / waterways |
| Transport | UN 1673; class 6.1; PG III; regulated dangerous good |
Certificate of Analysis (representative)
| Test parameter | Specification | Method |
|---|---|---|
| Assay (purity) | 99% min | GC / HPLC |
| Appearance | White to light-brown flakes | Visual |
| Melting point | 100–103 °C | Capillary |
| Isomer content (m- / p-PDA) | As per grade | GC |
| Moisture | 0.5% max | Karl Fischer |
The actual batch COA is supplied with each shipment.
FAQ
Frequently asked questions
Common questions from buyers specifying Ortho Phenylene Diamine for fungicide, pharmaceutical and specialty-chemical production.
What is Ortho Phenylene Diamine used for?
OPD is used mainly to make benzimidazole fungicides such as carbendazim, benomyl, thiophanate-methyl and thiabendazole. It is also used for benzimidazole and quinoxaline APIs, the corrosion inhibitor benzotriazole, the rubber antioxidant 2-mercaptobenzimidazole and pigment intermediates.
What is the CAS number of Ortho Phenylene Diamine?
The CAS number is 95-54-5 and the molecular formula is C6H8N2. It is also known as OPD, o-phenylenediamine, 1,2-diaminobenzene or benzene-1,2-diamine.
How is Ortho Phenylene Diamine manufactured?
2-Nitrochlorobenzene is reacted with ammonia to give ortho nitro aniline, and its nitro group is then reduced, usually by catalytic hydrogenation, to o-phenylenediamine.
Is Ortho Phenylene Diamine hazardous?
Yes. It is toxic if swallowed, harmful by skin contact and inhalation, a skin sensitiser, suspected of causing genetic defects and cancer, and very toxic to aquatic life. It must be handled with proper PPE, dust control and containment; we supply a full MSDS with every order.
Why does OPD turn brown?
OPD oxidises in air and light, forming coloured products. White to light-brown flakes indicate fresh material, which is why we ship in lined, nitrogen-flushed drums and recommend resealing promptly after use.
What is the difference between ortho, meta and para phenylenediamine?
Only the ortho isomer has its two amines side by side, so only OPD closes directly into benzimidazoles and benzotriazole. Meta- and para-phenylenediamine are used mainly for dyes, aramid fibres and rubber chemicals.
Do you provide COA and MSDS for OPD?
Yes, we provide a batch-specific COA and MSDS with every order, plus technical support on request.
Do you supply and export Ortho Phenylene Diamine?
Yes, we supply OPD across India and export internationally with complete documentation, sourced from reliable manufacturers.
Request a quote or sample
Need a reliable OPD supplier?
Looking for a dependable Ortho Phenylene Diamine (o-phenylenediamine) supplier and distributor — in India or anywhere we export to? Tell us the grade and quantity you need — our team responds with competitive bulk pricing, samples and complete documentation (COA, MSDS, TDS) within 24 hours.
Or email source@cheloraagrochem.com