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.

CAS number520-45-6
EC number208-293-9
Index number607-163-00-2
Molecular formulaC8H8O4
Molecular weight168.15 g/mol

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

  • dehydracetic acid

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 wordWarning
Hazard statements assigned to 3-acetyl-6-methyl-2H-pyran-2,4…
CodeHazard statement
H302 Harmful if swallowed.

Precautionary statements: P270, P301, P312, P330

03 · 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.

Property Value Conditions Source
Boiling point 269.9 °C (517.8 °F) at 760 mmHg HSDB
Melting point 110 °C (230 °F) range, midpoint shown HSDB
Solubility SOL IN ALKALIES HSDB
water solubility = 690 mg/l @ 25 °C at 25 °C HSDB
Vapor pressure 1.9 mmHg at 100 °C HSDB
Flash point 157 °C (314.6 °F) HSDB
Autoignition temperature 366 °C (690.8 °F) HSDB
Vapor density 5.8 (air = 1) HSDB

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

04 · Source notes

Further notes on 3-acetyl-6-methyl-2H-pyran-2,4…

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.

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

05 · Handling and storage

Storing 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 →

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