Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

O-Phenylenediamine

O-Phenylenediamine is brownish-yellow leaflets from water; plates from chloroform.

CAS 95-54-5 C6H8N2 108.14 g/mol Danger

01 · Identification

What O-Phenylenediamine is

O-Phenylenediamine is brownish-yellow leaflets from water; plates from chloroform. Its molecular formula is C6H8N2 and its molecular weight is 108.14 g/mol. It boils at 257 °C, melts at 102 °C.

Under the GHS it carries the signal word Danger.

CAS number95-54-5
EC number202-430-6
Index number612-145-00-2
Molecular formulaC6H8N2
Molecular weight108.14 g/mol

02 · GHS classification

Hazards and label elements

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Signal wordDanger
Hazard statements assigned to O-Phenylenediamine
CodeHazard statement
H351 Suspected of causing cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H341 Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H301 Toxic if swallowed.
H332 Harmful if inhaled.
H312 Harmful in contact with skin.
H319 Causes serious eye irritation.
H317 May cause an allergic skin reaction.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P201, P260, P261, P264, P270, P271, P272, P273, P280, P301, P302, P304, P305, P308, P310, P312, P313, P330, P333, P337, P338, P352, P391, P501

03 · Physical and chemical properties

O-Phenylenediamine properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Property Value Conditions Source
Boiling point 257 °C (494.6 °F) HSDB
257 °C (494.6 °F) at 760 mmHg DOE PAC
256.94 °C (494.5 °F) range, midpoint shown, at 760 mmHg CAMEO
Melting point 102.1 °C (215.8 °F) HSDB
104 °C (219.2 °F) DOE PAC
103.06 °C (217.5 °F) range, midpoint shown CAMEO
Solubility Because of ... limited solubility in cold water/o-phenylenediamine/ can be recrystalized from water HSDB
Freely soluble in alcohol, chloroform, ether HSDB
Soluble in water, ethyl ether, benzene, chloroform; very soluble in ethanol HSDB
Vapor pressure 0.0098 mmHg at 20 °C ICSC
0.0021 mmHg at 25 °C HSDB
Flash point 156 °C (312.8 °F) Closed cup HSDB
156.11 °C (313 °F) CAMEO
156 °C (312.8 °F) ICSC
Lower explosive limit (LEL) 1.5 % by volume HSDB
Finely dispersed particles form explosive mixtures in air. HSDB
Vapor density 3.73 (air = 1) ICSC

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Handling and storage

Storing and handling O-Phenylenediamine

Storage conditions

Separated from food and feedstuffs. Well closed.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

1,2-PHENYLENEDIAMINE a weak aromatic amine base neutralizes acids in exothermic reactions to form salts. May be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Darkens on exposure to air (Roger Patrick, DuPont Engineer).

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check O-Phenylenediamine in the storage compatibility matrix →

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