Dye IntermediateDG Class 6.1

2-Amino-4-Nitrophenol

Name: 2-Amino-4-Nitrophenol
Brand: Chelora Pharmachem
SKU: CAS-99-57-0
Availability: InStock

CAS 99-57-0 · C₆H₆N₂O₃ · MW 154.12

A key intermediate for oxidative hair dye formulations, azo dyes and pharmaceutical synthesis. Chelora supplies technical, cosmetic and pharma grades with certificate of analysis and full DG documentation on every batch.

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Technical / Cosmetic / Pharma grades
DG-compliant freight
Samples to bulk

2-Amino-4-Nitrophenol chemical manufacturing

Quality testing of 2-amino-4-nitrophenol

available grades

CAS number

99-57-0

Melting point

110 – 116 °C

Purity

≥ 98 %

Transport

UN 3143 · 6.1

Product overview

The colour chemistry workhorse

2-Amino-4-nitrophenol (also known as 2-hydroxy-5-nitroaniline or CI 76555) is an aromatic compound bearing both amino and nitro substituents on a phenol ring. It appears as an orange-yellow to dark red crystalline powder and is slightly soluble in water but readily dissolves in ethanol and dilute alkali solutions.

Its dominant commercial application is in the hair colour industry, where it functions as a primary intermediate (coupler) in permanent and semi-permanent oxidative hair dye systems. Under oxidation with hydrogen peroxide, it couples with developers such as p-phenylenediamine and p-aminophenol to produce warm red, copper, auburn and mahogany shades. The compound's electron-donating amino group and electron-withdrawing nitro group give formulators fine control over the shade produced.

Beyond hair colour, 2-amino-4-nitrophenol serves as a coupler and diazo component in azo dye manufacture for textile, leather and paper applications. In pharmaceutical chemistry it acts as a building block for heterocyclic synthesis and certain sulfonamide-class actives. Historical use in photographic colour-developing agents and ongoing utility in agrochemical intermediates round out its versatile applications.

The compound decomposes above its melting point (110 – 116 °C) and is classified as UN 3143, Class 6.1, Packing Group III for transport purposes. Chelora handles all DG logistics, documentation and freight on behalf of customers.

Technical specifications

IUPAC name2-Amino-4-nitrophenol

Synonyms2-Amino-4-nitrophenol, 2-Hydroxy-5-nitroaniline, CI 76555, 2A4NP

CAS number99-57-0

EC number202-768-1

Molecular formulaC₆H₆N₂O₃

Molecular weight154.12 g/mol

AppearanceOrange-yellow to dark red crystalline powder

Melting point110 – 116 °C (with decomposition)

Purity (assay)≥ 98.0 % (cosmetic grade)

Loss on drying≤ 1.0 %

Residue on ignition≤ 0.5 %

Heavy metals (as Pb)≤ 20 ppm

Solubility in waterSlightly soluble

Solubility in ethanolSoluble

Solubility in dilute alkaliFreely soluble

pH (1 % aqueous suspension)4.5 – 6.5

StorageCool, dry, ventilated area; protect from light and moisture

UN numberUN 3143

Transport classClass 6.1, Packing Group III

Applications & end uses

Industries that depend on 2-Amino-4-Nitrophenol

Hair dye intermediate (oxidative hair colorants)

2-Amino-4-nitrophenol is a primary intermediate in permanent and semi-permanent oxidative hair colour formulations. It couples with developers (e.g. p-phenylenediamine) during the oxidation step to produce warm red, auburn and mahogany shades across the colour spectrum.

Pharmaceutical intermediate

The compound serves as a versatile building block in the synthesis of pharmaceutical actives, including certain sulfonamide antibiotics and speciality drug candidates requiring a nitroaminophenol motif.

Azo dye manufacture

In the dye and pigment industry, 2-amino-4-nitrophenol is diazotised or used as a coupler in the manufacture of azo dyes for textile, leather and paper applications, producing fast colours with good wash and light resistance.

Photographic chemicals

Historically and in speciality photographic processes, the compound is employed as a component of colour-developing agents, contributing to the formation of colour-coupled dye images in silver-halide systems.

Organic synthesis building block

Researchers and process chemists use 2-amino-4-nitrophenol as a difunctional aromatic building block. The amino and nitro groups allow selective reduction, acylation, diazotisation and ring-closure reactions for heterocyclic synthesis.

Agricultural chemical intermediate

The compound enters the synthesis of certain agrochemical actives — including nitroaromatic herbicide and fungicide intermediates — where the aminophenol functionality provides the requisite reactivity for downstream coupling steps.

Available grades

Technical, cosmetic and pharmaceutical grades

≥ 97 %

Technical grade

Azo dyes, agrochemical intermediates, industrial synthesis

≥ 98 %

Cosmetic / hair dye grade

Oxidative hair colourants, semi-permanent dyes

≥ 99 %

Pharma grade

Pharmaceutical intermediates, R&D synthesis

Packaging options

UN-approved packaging for DG freight

25 kg — HDPE-lined fibre drum

Standard unit; Class 6.1 DG labelling applied

50 kg — HDPE-lined fibre drum

Bulk supply with UN-approved packaging

Sample — Sealed HDPE container (double-bagged)

QC evaluation prior to bulk commitment

Documentation supplied

Complete paperwork for QC, EHS and customs

Certificate of Analysis (COA)

Batch-specific results for assay, melting point, LOD, ROI, heavy metals and chromatographic purity.

Safety Data Sheet (SDS)

GHS-format, 16-section SDS covering DG classification, handling, first aid and disposal.

Specification sheet

Limit values for each test parameter aligned to cosmetic or pharmaceutical standards.

Transport documentation

UN 3143 Class 6.1 PG III documentation for DG freight and customs compliance.

Frequently asked questions

Common questions about 2-Amino-4-Nitrophenol

What is 2-Amino-4-Nitrophenol primarily used for?+

The dominant application is as an intermediate in permanent and semi-permanent oxidative hair dye formulations, where it couples with primary intermediates under oxidation to produce warm red and auburn shades. It is also used in azo dye manufacture, pharmaceutical synthesis and photographic chemicals.

Is 2-Amino-4-Nitrophenol classified as a dangerous good?+

Yes. It is classified as UN 3143, Class 6.1 (toxic substance, solid, organic), Packing Group III. Shipments are labelled and documented accordingly. Our logistics team handles all DG freight requirements and can arrange delivery to your door.

What purity grades does Chelora offer?+

We supply three grades: Technical (≥ 97 %) for industrial dye and agrochemical work, Cosmetic / hair dye grade (≥ 98 %) meeting colour-cosmetic industry requirements, and Pharma grade (≥ 99 %) for pharmaceutical intermediate and R&D applications. Each batch ships with a COA.

How should this product be stored?+

Store in a cool, dry, well-ventilated area away from direct sunlight, heat sources and incompatible materials (strong oxidisers, strong bases). Keep containers tightly closed. The material decomposes above its melting point (110 – 116 °C), so temperature control in warehousing is important.

Can I get a sample before placing a bulk order?+

Yes. We supply evaluation samples in sealed HDPE containers so your QC team can verify the material against your specification before you commit to a production order. Contact us with your grade requirement and application.

What is the typical lead time for a bulk order?+

Standard lead time is 7 – 12 working days for domestic orders and 12 – 18 days for export, accounting for DG freight requirements. We stock the cosmetic grade regularly and can often expedite for repeat customers.