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'-dimethoxybenzidine

3,3'-dimethoxybenzidine is leaflets or needles from water.

CAS 119-90-4 C14H16N2O2 244.29 g/mol Danger

01 · Identification

What 3,3'-dimethoxybenzidine is

3,3'-dimethoxybenzidine is leaflets or needles from water. Its molecular formula is C14H16N2O2 and its molecular weight is 244.29 g/mol. It melts at 137 °C.

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

CAS number119-90-4
EC number204-355-4
Index number612-036-00-X
Molecular formulaC14H16N2O2
Molecular weight244.29 g/mol
Chemical class Hazardous Air Pollutants (HAPs)

Other names for 3,3'-dimethoxybenzidine

  • o-dianisidine

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'-dimethoxybenzidine
CodeHazard statement
H350 May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H302 Harmful if swallowed.

Precautionary statements: P201, P270, P280, P301, P308, P312, P313, P330

03 · Physical and chemical properties

3,3'-dimethoxybenzidine 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
Melting point 137 °C (278.6 °F) HSDB
137.22 °C (279 °F) NIOSH
137.5 °C (279.5 °F) ICSC
Solubility Sol in alc, benzene, ether HSDB
Sol in chloroform, acetone HSDB
PROBABLY SOL IN MOST ORG SOLVENTS AND LIPIDS HSDB
Vapor pressure negligible ICSC
Flash point 206 °C (402.8 °F) HSDB
206.11 °C (403 °F) NIOSH
Lower explosive limit (LEL) The finely powdered carcinogen is a significant dust explosion hazard. HSDB
Combustible Solid NIOSH
Vapor density 8.43 (air = 1) HSDB
8.5 (air = 1) CAMEO

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

04 · Handling and storage

Storing and handling 3,3'-dimethoxybenzidine

Storage conditions

PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as practical to lab in which carcinogens are to be used, so that only small quantities required for ... expt need to be carried. Carcinogens should be kept in only one section of cupboard, an explosion-proof refrigerator or freezer (depending on chemicophysical properties ...) that bears appropriate label. An inventory ... should be kept, showing quantity of carcinogen & date it was acquired ... Facilities for dispensing ... should be contiguous to storage area. /Chemical Carcinogens/

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

... Can react with oxidizing materials.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

3,3'-DIMETHOXYBENZIDINE is a weak base. Reacts exothermically with acids. Sensitive to heat, air and prolonged exposure to light.

Source: CAMEO Chemicals

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

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