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-acetyl-6-methyl-2H-pyran-2,4(3H)-dione

3-acetyl-6-methyl-2H-pyran-2,4(3H)-dione is needles from water, rhombic needles or prisms from alcohol and is odorless.

CAS 520-45-6 C8H8O4 168.15 g/mol Warning

01 · Identification

What 3-acetyl-6-methyl-2H-pyran-2,4… is

3-acetyl-6-methyl-2H-pyran-2,4(3H)-dione is needles from water, rhombic needles or prisms from alcohol and is odorless. Its molecular formula is C8H8O4 and its molecular weight is 168.15 g/mol. It boils at 270 °C, melts at 110 °C.

Under the GHS it carries the signal word Warning.

02 · Identifiers

3-acetyl-6-methyl-2H-pyran-2,4… identifiers and molecular data

3-acetyl-6-methyl-2H-pyran-2,4… CAS number and EC number

CAS number520-45-6
EC number208-293-9
Index number (CLP Annex VI)607-163-00-2

3-acetyl-6-methyl-2H-pyran-2,4… molecular formula and molecular weight

Molecular formulaC8H8O4
Molecular weight168.15 g/mol

Other names for 3-acetyl-6-methyl-2H-pyran-2,4…

  • dehydracetic acid

03 · GHS classification

3-acetyl-6-methyl-2H-pyran-2,4… hazard classification

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

3-acetyl-6-methyl-2H-pyran-2,4… pictograms and signal word

Signal wordWarning

3-acetyl-6-methyl-2H-pyran-2,4… hazard class and category

GHS hazard classes 3-acetyl-6-methyl-2H-pyran… falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 4 H302 GHS07

3-acetyl-6-methyl-2H-pyran-2,4… hazard statements (H-codes)

Hazard statements assigned to 3-acetyl-6-methyl-2H-pyran…
CodeHazard statement
H302 Harmful if swallowed.

This page lists only the codes assigned to 3-acetyl-6-methyl-2H-pyran…. 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 3-acetyl-6-methyl-2H-pyran…

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 3-acetyl-6-methyl-2H-p… 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

3-acetyl-6-methyl-2H-pyran-2,4… precautionary statements

CLP Annex VI assigns 4 precautionary statements to 3-acetyl-6-methyl-2H-pyran…. 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.

Prevention

What to do before and during handling so the hazard never happens.

Response

What to do once exposure, spillage or fire has already happened.

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

3-acetyl-6-methyl-2H-pyran-2,4… 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 3-ацетил-6-метил-2 H -пиран-2,4(3 H )-дион дехидроцетна киселина
Spanish español 3-Acetil-6-metil-2 H -pirano-2,4(3 H )-diona ácido dehidroacético
Czech čeština 3-acetyl-6-methyltetrahydropyran-2,4-dion dehydracetová kyselina
Danish dansk 3-acetyl-6-methyl-2 H- pyran-2,4(3 H) -dion dehydracetsyre
German Deutsch 3-Acetyl-6-methyl-2 H -pyran-2,4(3 H )-dion Dehydracetsäure
Estonian eesti 3-atsetüül-6-metüül-2 H -püraan-2,4(3 H )-dioon dehüdroäädikhape
Greek ελληνικά 3-ακετυλο-6-μεθυλο-2 H -πυρανο-2,4(3 H )-διόνη δεϋδροξικό οξύ
English English 3-acetyl-6-methyl-2 H -pyran-2,4(3 H )-dione dehydracetic acid
French français 3-acétyl-6-méthyl-2 H -pyran-2,4(3 H )-dione acide déhydroacétique
Croatian hrvatski 3-acetil-6-metil-2 H -piran-2,4(3 H )-dion dehidrooctena kiselina
Italian italiano 3-acetil-6-metil-2 H -piran-2,4(3 H )-dione acido deidroacetico
Latvian latviešu 3-acetil-6-metil-2 H -pirān-2,4(3 H )-dions dehidroetiķskābe
Lithuanian lietuvių 3-acetil-6-metil-2 H -piran-2,4(3 H )-dionas dehidracto rūgštis
Hungarian magyar 3-acetil-6-metil-2 H -pirán-2,4(3 H )-dion dehidrecetsav
Maltese Malti 3-aċetil-6-metil-2 H -piran-2,4(3 H )-dion aċidu deidraċetiku
Dutch Nederlands 3-acetyl-6-methyl-2 H -pyran-2,4(3 H )-dion dehydroazijnzuur
Polish polski 3-acetylo-6-metylo-2 H -pirano-2,4(3 H )-dion kwas dehydrooctowy
Portuguese português 3-acetil-6-metil-2 H -pirano-2,4(3 H )-diona ácido desidroacético
Romanian română 3-acetil-6-metil-2 H -piran-2,4(3 H )-dionă acid dehidracetic
Slovak slovenčina 3-acetyl-6-metyl-2 H -pyrán-2,4(3 H )-dión kyselina dehydracetová
Slovenian slovenščina 3-acetil-6-metil-2 H -piran-2,4(3 H )-dion dehidrocetna kislina
Finnish suomi 3-asetyyli-6-metyyli-2 H -pyraani-2,4(3 H )-dioni dehydroetikkahappo
Swedish svenska 3-acetyl-6-metyl-2 H -pyran-2,4(3 H )-dion dehydroättiksyra

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

3-acetyl-6-methyl-2H-pyran-2,4… GHS label elements

Everything CLP Annex VI fixes for 3-acetyl-6-methyl-2H-pyran…, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS07 Exclamation mark pictogram

Warning

3-acetyl-6-methyl-2H-pyran-2,4…

  • Harmful if swallowed.
  • Do not eat, drink or smoke when using this product.
  • IF SWALLOWED:
  • Call a POISON CENTER/doctor/ if you feel unwell.
  • Rinse mouth.

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

Need this as an actual label? Open 3-acetyl-6-methyl-2H-pyran… in the GHS label constructor →

07 · Physical and chemical properties

3-acetyl-6-methyl-2H-pyran-2,4… 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.

3-acetyl-6-methyl-2H-pyran-2,4… boiling point

Property Value Conditions Source
Boiling point 269.9 °C (517.8 °F) at 760 mmHg HSDB

3-acetyl-6-methyl-2H-pyran-2,4… melting point

Property Value Conditions Source
Melting point 110 °C (230 °F) range, midpoint shown HSDB

3-acetyl-6-methyl-2H-pyran-2,4… solubility

Property Value Conditions Source
Solubility SOL IN ALKALIES HSDB
water solubility = 690 mg/l @ 25 °C at 25 °C HSDB

3-acetyl-6-methyl-2H-pyran-2,4… vapor pressure

Property Value Conditions Source
Vapor pressure 1.9 mmHg at 100 °C HSDB

3-acetyl-6-methyl-2H-pyran-2,4… flash point

Property Value Conditions Source
Flash point 157 °C (314.6 °F) HSDB

3-acetyl-6-methyl-2H-pyran-2,4… autoignition temperature

Property Value Conditions Source
Autoignition temperature 366 °C (690.8 °F) HSDB

3-acetyl-6-methyl-2H-pyran-2,4… vapor density

Property Value Conditions Source
Vapor density 5.8 (air = 1) HSDB

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

08 · Fire and explosion

3-acetyl-6-methyl-2H-pyran… fire and explosion behaviour

These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.

3-acetyl-6-methyl-2H-pyran-2,4… fire potential

SLIGHT

Source: Hazardous Substances Data Bank (HSDB)

Solubility

(WT/WT) 22% IN ACETONE, 18% IN BENZENE, 5% IN METHANOL, 3% IN USP ETHANOL, 3% IN CARBON TETRACHLORIDE, 5% IN ETHER, 0.7% IN N-HEPTANE, LESS THAN 0.1% IN GLYCEROL, 1.6% IN OLIVE OIL, 1.7% IN PROPYLENE GLYCOL, LESS THAN 0.1% IN WATER AT 25 °C

Source: HSDB

09 · Handling and storage

3-acetyl-6-methyl-2H-pyran-2,4… storage and handling

3-acetyl-6-methyl-2H-pyran-2,4… incompatible materials

HIGHLY REACTIVE

Source: Hazardous Substances Data Bank (HSDB)

Planning storage for a mix of chemicals? Check 3-acetyl-6-methyl-2H-pyra… in the storage compatibility matrix →

10 · Questions

3-acetyl-6-methyl-2H-pyran-2,4… — frequently asked questions

What is the CAS number of 3-acetyl-6-methyl-2H-pyran-2,4…?

The CAS number of 3-acetyl-6-methyl-2H-pyran-2,4… is 520-45-6. Its EC number is 208-293-9.

What is the chemical formula of 3-acetyl-6-methyl-2H-pyran-2,4…?

The molecular formula of 3-acetyl-6-methyl-2H-pyran-2,4… is C8H8O4 and its molecular weight is 168.15 g/mol.

What does a 3-acetyl-6-methyl-2H-pyran-2,4… label have to show?

Under CLP Annex VI the label for 3-acetyl-6-methyl-2H-pyran-2,4… carries the pictogram Exclamation mark and the signal word is Warning.

Is 3-acetyl-6-methyl-2H-pyran-2,4… flammable?

CLP Annex VI assigns 3-acetyl-6-methyl-2H-pyran-2,4… 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 157 °C (314.6 °F) (HSDB).

Is 3-acetyl-6-methyl-2H-pyran-2,4… a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for 3-acetyl-6-methyl-2H-pyran-2,4…. 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 3-acetyl-6-methyl-2H-pyran-2,4…?

The boiling point reported for 3-acetyl-6-methyl-2H-pyran-2,4… is 269.9 °C (517.8 °F), at 760 mmHg (HSDB).

What is the melting point of 3-acetyl-6-methyl-2H-pyran-2,4…?

The melting point reported for 3-acetyl-6-methyl-2H-pyran-2,4… is 110 °C (230 °F), range, midpoint shown (HSDB).

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