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.

02 · Identifiers

1,4-Dichloro-2-butene identifiers and molecular data

1,4-Dichloro-2-butene CAS number and EC number

CAS number764-41-0
EC number212-121-8
Index number (CLP Annex VI)602-073-00-X

1,4-Dichloro-2-butene molecular formula and molecular weight

Molecular formulaC4H6Cl2
Molecular weight124.99 g/mol

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

  • 1,4-dichlorobut-2-ene

03 · GHS classification

1,4-Dichloro-2-butene hazard classification

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

1,4-Dichloro-2-butene pictograms and signal word

Signal wordDanger

1,4-Dichloro-2-butene hazard class and category

GHS hazard classes 1,4-Dichloro-2-butene falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 3 H301 GHS06
Acute toxicity - dermal GHS chapter 3.1 Category 3 H311 GHS06
Acute toxicity - inhalation GHS chapter 3.1 Category 1 or 2 H330 GHS06
Skin corrosion/irritation GHS chapter 3.2 Category 1A or 1B or 1C H314 GHS05
Carcinogenicity GHS chapter 3.6 Category 1A or 1B H350 GHS08
Hazardous to the aquatic environment - acute GHS chapter 4.1 Category 1 H400 GHS09
Hazardous to the aquatic environment - chronic GHS chapter 4.1 Category 1 H410 GHS09

Where two values are shown with “or”, the hazard statement is shared by more than one category or by more than one class, and the code alone does not say which. H272, for example, belongs to oxidising liquids and to oxidising solids — the physical state decides. The binding answer for a specific entry is in the CLP Annex VI table itself.

1,4-Dichloro-2-butene hazard statements (H-codes)

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.

This page lists only the codes assigned to 1,4-Dichloro-2-butene. The full reference lives on the hazard statements hub, the precautionary statements hub and the GHS pictograms hub.

Safety Data Sheet

Getting an SDS for 1,4-Dichloro-2-butene

A Safety Data Sheet is written for a product, not for a substance: the supplier of the grade you actually buy issues it, so two suppliers of 1,4-Dichloro-2-butene issue two different sheets. That is why there is no single authoritative SDS for a substance to download — what there is, is the job of collecting the sheets for the products you hold and keeping them current as suppliers revise them.

04 · Precautionary statements

1,4-Dichloro-2-butene precautionary statements

CLP Annex VI assigns 17 precautionary statements to 1,4-Dichloro-2-butene. They are grouped the way a label groups them: what to do before handling, what to do when something has already happened, how to store it and how to dispose of it.

Disposal

What has to happen to the contents and the empty container.

Reading the notation. is a blank the supplier fills in — not a truncated sentence.· [square brackets] mark a part printed only when it applies.

05 · Names in the regulation

1,4-Dichloro-2-butene name in 23 EU languages

CLP Annex VI Part 3 is published in every language edition of the regulation, and the identification column is written out in each of them. Nothing below is translated by us: each line is the name as that edition prints it. Under Art. 18(2) the substance name from Annex VI is a lawful product identifier, so this is the wording to put on a label going to that market — and where the cell lists several designations, any one of them qualifies.

Language Name in CLP Annex VI Part 3
Bulgarian български 1,4-дихлоробут-2-ен
Spanish español 1,4-Diclorobut-2-eno
Czech čeština 1,4-dichlorbut-2-en
Danish dansk 1,4-dichlorbut-2-en
German Deutsch 1,4-Dichlorbut-2-en 1,4-Dichlorbuten-2
Estonian eesti 1,4-diklorobut-2-een
Greek ελληνικά 1,4-διχλωροβουτ-2-ένιο
English English 1,4-dichlorobut-2-ene
French français 1,4-dichlorobut-2-ène
Croatian hrvatski 1,4-diklorbut-2-en
Italian italiano 1,4-diclorobut-2-ene
Latvian latviešu 1,4-dihlorbut-2-ēns
Lithuanian lietuvių 1,4-dichlorbut-2-enas
Hungarian magyar 1,4-diklórbut-2-én
Maltese Malti 1,4-diklorobut-2-en
Dutch Nederlands 1,4-dichloorbut-2-een
Polish polski 1,4-dichlorobut-2-en
Portuguese português 1,4-diclorobut-2-eno
Romanian română 1,4-diclorbut-2-enă
Slovak slovenčina 1,4-dichlórbut-2-én
Slovenian slovenščina 1,4-diklorobut-2-en
Finnish suomi 1,4-diklooribut-2-eeni
Swedish svenska 1,4-diklorbut-2-en

All 23 language editions of Annex VI carry this entry. Irish is the twenty-fourth official EU language and has no line here for a different reason: no consolidated CLP text has ever been published in Irish, so there is no Irish edition of Annex VI to quote a name from. Source: consolidated CLP, CELEX 02008R1272, language editions. © European Union, https://eur-lex.europa.eu — only the electronic Official Journal of the European Union is authentic.

06 · Label elements

1,4-Dichloro-2-butene GHS label elements

Everything CLP Annex VI fixes for 1,4-Dichloro-2-butene, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS06 Skull and crossbones pictogramGHS08 Health hazard pictogramGHS05 Corrosion pictogramGHS09 Environment pictogram

Danger

1,4-Dichloro-2-butene

  • May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
  • Fatal if inhaled.
  • Toxic in contact with skin.
  • Toxic if swallowed.
  • Causes severe skin burns and eye damage.
  • Very toxic to aquatic life.
  • Very toxic to aquatic life with long lasting effects.
  • Obtain special instructions before use.
  • Do not breathe dust/fume/gas/mist/vapours/spray.
  • Do not eat, drink or smoke when using this product.
  • Use only outdoors or in a well-ventilated area.
  • Avoid release to the environment.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF SWALLOWED:
  • IF ON SKIN:
  • IF INHALED:
  • IF exposed or concerned:
  • Immediately call a POISON CENTER/doctor/
  • Get medical advice/attention.
  • Rinse mouth.
  • Do NOT induce vomiting.
  • Wash with plenty of water/
  • Collect spillage.
  • Dispose of contents/container to

Supplier name, address and telephone number· Product identifier·Nominal quantity

Need this as an actual label? Open 1,4-Dichloro-2-butene in the GHS label constructor →

07 · Health hazards

1,4-Dichloro-2-butene health hazards and exposure limits

1,4-Dichloro-2-butene hazard summary

Highly toxic; [Quick CPC] When heated, decomposes to toxic gases: phosgene and HCl; High inhalation exposure can cause pulmonary edema; [HSDB] Skin contact with liquid causes severe blistering; [CHRIS] Induces genetic damage in germ cells of humans or animals (3A); [MAK] Reacts with water forming hydrochloric acid; Vapor is irritating to nose and throat; Highly irritating to skin (blistering) and eyes (lachrymation); [CAMEO] Generally available in the US as a mixture of 95-98% trans- (CAS# 110-57-6) and 2-5% cis- (CAS#1476-11-5) isomers; [OECD SIDS] Causes burns and lachrymation; Inhalation may cause corrosive injuries to upper respiratory tract and lungs; Highly toxic by inhalation; Toxic by ingestion and skin absorption; [Aldrich MSDS] See 1,4-Dichloro-trans-2-butene.

Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

1,4-Dichloro-2-butene carcinogenicity classification

Classification of carcinogenicity: evidence in animals: inadequate. No epidemiological data relevant to the carcinogenicity of trans-1,4-dichlorobutene were available. Overall summary evaluation of carcinogenic risk to humans is Group 3. The agent is not classifiable as to its carcinogenicity to humans.

Source: Hazardous Substances Data Bank (HSDB)

An IARC group and a CLP classification answer different questions. IARC judges whether the evidence for cancer in humans is strong enough; CLP Annex VI is the legally binding EU classification. A substance can carry one and not the other.

08 · 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.

1,4-Dichloro-2-butene boiling point

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

1,4-Dichloro-2-butene melting point

Property Value Conditions Source
Melting point 3.5 °C (38.3 °F) HSDB
-47.78 °C (-54 °F) CAMEO

1,4-Dichloro-2-butene density

Property Value Conditions Source
Density 1.1858 g/cm³ HSDB
1.183 g/cm³ technical grade mixture HSDB
1.112 g/cm³ at 20 °C CAMEO

1,4-Dichloro-2-butene solubility

Property Value Conditions Source
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

1,4-Dichloro-2-butene vapor pressure

Property Value Conditions Source
Vapor pressure 3 mmHg at 25 °C HSDB
3 mmHg Haz-Map

1,4-Dichloro-2-butene lower explosive limit (LEL)

Property Value Conditions Source
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

1,4-Dichloro-2-butene upper explosive limit (UEL)

Property Value Conditions Source
Upper explosive limit (UEL) 4 % by volume CAMEO

1,4-Dichloro-2-butene corrosivity

Property Value Conditions Source
Corrosivity Corrodes metal when wet. Dichlorobutene HSDB

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

09 · Handling and storage

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

1,4-Dichloro-2-butene storage conditions

Storage temperature: ambient /Dichlorobutene/

Source: Hazardous Substances Data Bank (HSDB)

1,4-Dichloro-2-butene incompatible materials

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

Source: Hazardous Substances Data Bank (HSDB)

1,4-Dichloro-2-butene 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 →

10 · Questions

1,4-Dichloro-2-butene — frequently asked questions

What is the CAS number of 1,4-Dichloro-2-butene?

The CAS number of 1,4-Dichloro-2-butene is 764-41-0. Its EC number is 212-121-8.

What is the chemical formula of 1,4-Dichloro-2-butene?

The molecular formula of 1,4-Dichloro-2-butene is C4H6Cl2 and its molecular weight is 124.99 g/mol.

What does a 1,4-Dichloro-2-butene label have to show?

Under CLP Annex VI the label for 1,4-Dichloro-2-butene carries the pictograms Skull and crossbones, Health hazard, Corrosion and Environment and the signal word is Danger.

Is 1,4-Dichloro-2-butene flammable?

CLP Annex VI assigns 1,4-Dichloro-2-butene no flammability hazard class. That is not a statement that it cannot burn: the harmonised list only records the hazards that were assessed for it.

Is 1,4-Dichloro-2-butene a carcinogen?

Yes. CLP Annex VI classifies 1,4-Dichloro-2-butene as a category 1A or 1B carcinogen and assigns it H350: may cause cancer.

What is the boiling point of 1,4-Dichloro-2-butene?

The boiling point reported for 1,4-Dichloro-2-butene is 158 °C (316.4 °F) (HSDB).

What is the melting point of 1,4-Dichloro-2-butene?

The melting point reported for 1,4-Dichloro-2-butene is 3.5 °C (38.3 °F) (HSDB).

How should 1,4-Dichloro-2-butene be stored?

Storage temperature: ambient /Dichlorobutene/ (Hazardous Substances Data Bank (HSDB))

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