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

1,4-Dichloro-2-butene

1,4-Dichloro-2-butene is a colorless liquid with a sweet, pungent odor.

CAS 764-41-0 C4H6Cl2 124.99 g/mol Danger

01 · Identification

What 1,4-Dichloro-2-butene is

1,4-Dichloro-2-butene is a colorless liquid with a sweet, pungent odor. Its molecular formula is C4H6Cl2 and its molecular weight is 124.99 g/mol. It boils at 158 °C, melts at 3.5 °C, is soluble in water.

Under the GHS it carries the signal word Danger.

CAS number764-41-0
EC number212-121-8
Index number602-073-00-X
Molecular formulaC4H6Cl2
Molecular weight124.99 g/mol

Other names for 1,4-Dichloro-2-butene

  • 1,4-dichlorobut-2-ene

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 1,4-Dichloro-2-butene
CodeHazard statement
H350 May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H330 Fatal if inhaled.
H311 Toxic in contact with skin.
H301 Toxic if swallowed.
H314 Causes severe skin burns and eye damage.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P201, P260, P270, P271, P273, P280, P301, P302, P304, P308, P310, P313, P330, P331, P352, P391, P501

03 · Physical and chemical properties

1,4-Dichloro-2-butene 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 158 °C (316.4 °F) HSDB
156.11 °C (313 °F) at 760 mmHg CAMEO
158 °C (316.4 °F) at 760 mmHg DOE PAC
Melting point 3.5 °C (38.3 °F) HSDB
-47.78 °C (-54 °F) CAMEO
Density 1.1858 g/cm³ HSDB
1.183 g/cm³ technical grade mixture HSDB
1.112 g/cm³ at 20 °C CAMEO
Solubility Miscible with benzene, alc, carbon tetrachloride; immiscible with ethylene glycol and glycerol. HSDB
Soluble in ether. HSDB
Water solubility = 580 mg/l at 25 °C at 25 °C HSDB
Vapor pressure 3 mmHg at 25 °C HSDB
3 mmHg Haz-Map
Lower explosive limit (LEL) 1.5 % by volume CAMEO
1.5-4.0% Dichlorobutene HSDB
Vapor may explode if ignited in an enclosed area. Dichlorobutene HSDB
Upper explosive limit (UEL) 4 % by volume CAMEO
Corrosivity Corrodes metal when wet. Dichlorobutene HSDB

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

04 · Handling and storage

Storing and handling 1,4-Dichloro-2-butene

Storage conditions

Storage temperature: ambient /Dichlorobutene/

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

/Dichlorobutene/ reacts slowly with water to form hydrochloric acid. /Dichlorobutene/

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

Halogenated unsaturated aliphatic compounds, such as 1,4-DICHLORO-2-BUTENE, are moderately or very reactive. Halogenated organics generally become less reactive as more of their hydrogen atoms are replaced with halogen atoms. Low molecular weight haloalkanes are highly flammable and can react with some metals to form dangerous products. Materials in this group are incompatible with strong oxidizing and reducing agents. Also, they are incompatible with many amines, nitrides, azo/diazo compounds, alkali metals, and epoxides.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check 1,4-Dichloro-2-butene in the storage compatibility matrix →

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