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

3,3'-Dichlorobenzidine

3,3'-Dichlorobenzidine is needles from alcohol or benzene.

CAS 91-94-1 C12H10Cl2N2 253.12 g/mol Danger

01 · Identification

What 3,3'-Dichlorobenzidine is

3,3'-Dichlorobenzidine is needles from alcohol or benzene. Its molecular formula is C12H10Cl2N2 and its molecular weight is 253.12 g/mol. It boils at 420 °C, melts at 133 °C.

Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).

CAS number91-94-1
EC number202-109-0
Index number612-068-00-4
Molecular formulaC12H10Cl2N2
Molecular weight253.12 g/mol
Chemical class Hazardous Air Pollutants (HAPs)

Other names for 3,3'-Dichlorobenzidine

  • 3,3'-dichlorobiphenyl-4,4'-ylenediamine

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 3,3'-Dichlorobenzidine
CodeHazard statement
H350 May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H312 Harmful in contact with skin.
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, P261, P272, P273, P280, P302, P308, P312, P313, P333, P352, P391, P501

03 · Physical and chemical properties

3,3'-Dichlorobenzidine 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 420 °C (788 °F) NIOSH
420 °C (788 °F) at 760 mmHg CAMEO
368 °C (694.4 °F) ICSC
Melting point 132.5 °C (270.5 °F) HSDB
132.78 °C (271 °F) NIOSH
Solubility Solubility in water: 2-4% at 22 °C and pH 4.6 to pH 8.9 at 22 °C, Dihydrochloride salt HSDB
Moderately soluble in alcohol; readily soluble in ether HSDB
In water, 3.1 mg/L at 25 °C at 25 °C HSDB
Autoignition temperature 350 °C (662 °F) ICSC

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

04 · Handling and storage

Storing and handling 3,3'-Dichlorobenzidine

Storage conditions

Stable under recommended storage conditions.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Strong oxidizing agents

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

A halide- and amine-substituted aromatic compound. Amines are chemical bases. They neutralize acids to form salts plus water. These acid-base reactions are exothermic. The amount of heat that is evolved per mole of amine in a neutralization is largely independent of the strength of the amine as a base. Amines may be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen is generated by amines in combination with strong reducing agents, such as hydrides.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check 3,3'-Dichlorobenzidine in the storage compatibility matrix →

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