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

2-Butyne-1,4-diol

2-Butyne-1,4-diol is plates from benzene and ethyl acetate.

CAS 110-65-6 C4H6O2 86.09 g/mol Danger

01 · Identification

What 2-Butyne-1,4-diol is

2-Butyne-1,4-diol is plates from benzene and ethyl acetate. Its molecular formula is C4H6O2 and its molecular weight is 86.09 g/mol. It boils at 238 °C, melts at 50 °C, is soluble in water.

Under the GHS it carries the signal word Danger. It is classed as reactive agents - 1st degree.

02 · Identifiers

2-Butyne-1,4-diol identifiers and molecular data

2-Butyne-1,4-diol CAS number and EC number

CAS number110-65-6
EC number203-788-6
Index number (CLP Annex VI)603-076-00-9

2-Butyne-1,4-diol molecular formula and molecular weight

Molecular formulaC4H6O2
Molecular weight86.09 g/mol
Chemical class Reactive agents - 1st degree

Other names for 2-Butyne-1,4-diol

  • but-2-yne-1,4-diol

03 · GHS classification

2-Butyne-1,4-diol hazard classification

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

2-Butyne-1,4-diol pictograms and signal word

Signal wordDanger

2-Butyne-1,4-diol hazard class and category

GHS hazard classes 2-Butyne-1,4-diol 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 4 H312 GHS07
Acute toxicity - inhalation GHS chapter 3.1 Category 3 H331 GHS06
Skin corrosion/irritation GHS chapter 3.2 Category 1A or 1B or 1C H314 GHS05
Skin sensitisation GHS chapter 3.4 Category 1 or 1A or 1B H317 GHS07
Specific target organ toxicity - repeated exposure GHS chapter 3.9 Category 2 H373 GHS08

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.

2-Butyne-1,4-diol hazard statements (H-codes)

Hazard statements assigned to 2-Butyne-1,4-diol
CodeHazard statement
H331 Toxic if inhaled.
H301 Toxic if swallowed.
H312 Harmful in contact with skin.
H373 May cause damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H314 Causes severe skin burns and eye damage.
H317 May cause an allergic skin reaction.

This page lists only the codes assigned to 2-Butyne-1,4-diol. 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 2-Butyne-1,4-diol

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 2-Butyne-1,4-diol 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

2-Butyne-1,4-diol precautionary statements

CLP Annex VI assigns 17 precautionary statements to 2-Butyne-1,4-diol. 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.

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

2-Butyne-1,4-diol 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 бут-2-ин-1,4-диол 2-бутин-1,4-диол
Spanish español But-2-ino-1,4-diol 2-butino-1,4-diol
Czech čeština but-2-yn-1,4-diol 2-butyn-1,4-diol
Danish dansk but-2-yn-1,4-diol 2-butyn-1,4-diol
German Deutsch But-2-in-1,4-diol 2-Butin-1,4-diol
Estonian eesti but-2-üün-1,4-diool 2-butüün-1,4-diool
Greek ελληνικά βουτ-2-ινο-1,4-διόλη 2-βουτινο-1,4-διόλη
English English but-2-yne-1,4-diol 2-butyne-1,4-diol
French français but-2-yne-1,4-diol 2-butyne-1,4-diol
Croatian hrvatski but-2-in-1,4-diol 2-butin-1,4-diol
Italian italiano but-2-in-1,4-diolo 2-butin-1,4-diolo
Latvian latviešu but-2-īn-1,4-diols 2-butīn-1,4-diols
Lithuanian lietuvių but-2-in-1,4-diolis 2-butin-1,4-diolis
Hungarian magyar but-2-in-1,4-diol 2-butin-1,4-diol
Maltese Malti but-2-ine-1,4-diol 2-butine-1,4-diol
Dutch Nederlands but-2-yn-1,4-diol 2-butyn-1,4-diol
Polish polski but-2-yno-1,4-diol 2-butyno-1,4-diol
Portuguese português but-2-ino-1,4-diol 2-butino-1,4-diol
Romanian română but-2-in-1,4-diol 2-butin-1,4-diol
Slovak slovenčina but-2-ín-1,4-diol 2-butín-1,4-diol
Slovenian slovenščina but-2-in-1,4-diol 2-butin-1,4-diol
Finnish suomi but-2-yyni-1,4-dioli 2-butyyni-1,4-dioli
Swedish svenska but-2-yn-1,4-diol 2-butyn-1,4-diol

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

2-Butyne-1,4-diol GHS label elements

Everything CLP Annex VI fixes for 2-Butyne-1,4-diol, 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 pictogramGHS05 Corrosion pictogramGHS08 Health hazard pictogram

Danger

2-Butyne-1,4-diol

  • Toxic if inhaled.
  • Toxic if swallowed.
  • Harmful in contact with skin.
  • May cause damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
  • Causes severe skin burns and eye damage.
  • May cause an allergic skin reaction.
  • Do not breathe dust/fume/gas/mist/vapours/spray.
  • Avoid breathing 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.
  • Contaminated work clothing should not be allowed out of the workplace.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF SWALLOWED:
  • IF ON SKIN:
  • IF INHALED:
  • Immediately call a POISON CENTER/doctor/
  • Call a POISON CENTER/doctor/ if you feel unwell.
  • Get medical advice/attention.
  • Get medical advice/attention if you feel unwell.
  • Rinse mouth.
  • Do NOT induce vomiting.
  • If skin irritation or rash occurs:
  • Wash with plenty of water/

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

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

07 · Health hazards

2-Butyne-1,4-diol health hazards and exposure limits

2-Butyne-1,4-diol hazard summary

A severe skin and eye irritant; [HSDB] Toxic by inhalation, ingestion, and skin contact; [CAMEO] May cause skin burns and sensitization; [eChemPortal: ESIS] A corrosive substance that can cause injury to the skin, eyes, and respiratory tract; Inhalation may cause chemical pneumonitis; May cause skin sensitization; Causes liver, brain, and reproductive injury in high-dose animal studies; [MSDSonline] Danger of cutaneous absorption; Danger of skin sensitization; [MAK]

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

08 · Physical and chemical properties

2-Butyne-1,4-diol 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.

2-Butyne-1,4-diol boiling point

Property Value Conditions Source
Boiling point 238 °C (460.4 °F) HSDB
237.78 °C (460 °F) at 760 mmHg CAMEO
238 °C (460.4 °F) at 760 mmHg DOE PAC

2-Butyne-1,4-diol melting point

Property Value Conditions Source
Melting point 50 °C (122 °F) HSDB
58 °C (136.4 °F) ICSC

2-Butyne-1,4-diol density

Property Value Conditions Source
Density 1.1 g/cm³ ICSC
1.115 g/cm³ at 20 °C HSDB
1.07 g/cm³ at 20 °C CAMEO

2-Butyne-1,4-diol solubility

Property Value Conditions Source
Solubility Insoluble in benzene; slightly soluble in ethyl ether, choroform; very soluble in ethanol, acetone, methanol HSDB
Soluble in aqueous acids. HSDB
In water, 3.74X10+6 mg/L at 25 °C at 25 °C HSDB

2-Butyne-1,4-diol vapor pressure

Property Value Conditions Source
Vapor pressure 0.0015 mmHg at 20 °C ICSC
0.000556 mmHg at 25 °C HSDB
0.000556 mmHg Haz-Map

2-Butyne-1,4-diol flash point

Property Value Conditions Source
Flash point 128.33 °C (263 °F) HSDB
152 °C (305.6 °F) ICSC

2-Butyne-1,4-diol autoignition temperature

Property Value Conditions Source
Autoignition temperature 335 °C (635 °F) ICSC

2-Butyne-1,4-diol lower explosive limit (LEL)

Property Value Conditions Source
Lower explosive limit (LEL) Explosive reaction with traces of alkalies, alkali earth hydroxides, halide salts, strong acids, mercury salts plus strong acids. HSDB

2-Butyne-1,4-diol vapor density

Property Value Conditions Source
Vapor density 3 (air = 1) ICSC

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

09 · Handling and storage

2-Butyne-1,4-diol storage and handling

2-Butyne-1,4-diol safe storage

Separated from incompatible materials. See Chemical Dangers. Cool. Store in an area without drain or sewer access.

Source: ILO-WHO International Chemical Safety Cards (ICSCs)

2-Butyne-1,4-diol storage conditions

The storage temperature should be kept below 40 °C and storage times longer than a few months should be avoided because the butynediol flakes tend to set up.

Source: Hazardous Substances Data Bank (HSDB)

2-Butyne-1,4-diol incompatible materials

The pure diol may be distilled unchanged, but traces of alkali or alkaline earth hydroxides or halides may cause explosive decomposition during distillation. In presence of strong acids, mercury salts may cause violent decomposition of the diol.

Source: Hazardous Substances Data Bank (HSDB)

2-Butyne-1,4-diol reactivity

Pure 1,4-BUTYNEDIOL is non-explosive. Small amounts of certain impurities-alkali hydroxides, alkaline earth hydroxides, halides-may cause explosive decomposition upon distillation. Butynediol should not be treated with basic catalysts in the absence of a solvent at room temperature, and its stability is less with elevated temperatures. In strong acids, contamination with mercury salts can also result in violent decomposition. [NFPA 491M 1991].

Source: CAMEO Chemicals

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

10 · Questions

2-Butyne-1,4-diol — frequently asked questions

What is the CAS number of 2-Butyne-1,4-diol?

The CAS number of 2-Butyne-1,4-diol is 110-65-6. Its EC number is 203-788-6.

What is the chemical formula of 2-Butyne-1,4-diol?

The molecular formula of 2-Butyne-1,4-diol is C4H6O2 and its molecular weight is 86.09 g/mol.

What does a 2-Butyne-1,4-diol label have to show?

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

Is 2-Butyne-1,4-diol flammable?

CLP Annex VI assigns 2-Butyne-1,4-diol 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. The flash point reported for it is 128.33 °C (263 °F) (HSDB).

Is 2-Butyne-1,4-diol a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for 2-Butyne-1,4-diol. Annex VI is a list of agreed classifications, not a list of substances found safe, so this is an absence of a classification rather than a clean bill of health.

What is the boiling point of 2-Butyne-1,4-diol?

The boiling point reported for 2-Butyne-1,4-diol is 238 °C (460.4 °F) (HSDB).

What is the melting point of 2-Butyne-1,4-diol?

The melting point reported for 2-Butyne-1,4-diol is 50 °C (122 °F) (HSDB).

How should 2-Butyne-1,4-diol be stored?

The storage temperature should be kept below 40 °C and storage times longer than a few months should be avoided because the butynediol flakes tend to set up. (Hazardous Substances Data Bank (HSDB))

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