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-methyl-4-oxo-3-(penta-2,4-dienyl)cyclopent-2-enyl [1R-[1α[S*(Z)],3β]]-chrysanthemate

2-methyl-4-oxo-3-(penta-2,4-dienyl)cyclopent-2-enyl [1R-[1α[S*(Z)],3β]]-chrysanthemate is a viscous liquid.

CAS 121-21-1 C21H28O3 328.4 g/mol Warning

01 · Identification

What 2-methyl-4-oxo-3-(penta-2,4-di… is

2-methyl-4-oxo-3-(penta-2,4-dienyl)cyclopent-2-enyl [1R-[1α[S*(Z)],3β]]-chrysanthemate is a viscous liquid. Its molecular formula is C21H28O3 and its molecular weight is 328.4 g/mol. It is soluble in water.

Under the GHS it carries the signal word Warning.

CAS number121-21-1
EC number204-455-8
Index number613-023-00-1
Molecular formulaC21H28O3
Molecular weight328.4 g/mol

Other names for 2-methyl-4-oxo-3-(penta-2,4-di…

  • pyrethrin I

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 2-methyl-4-oxo-3-(penta-2,4-di…
CodeHazard statement
H332 Harmful if inhaled.
H312 Harmful in contact with skin.
H302 Harmful if swallowed.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P260, P270, P271, P273, P280, P301, P302, P304, P312, P330, P352, P391, P501

03 · Physical and chemical properties

2-methyl-4-oxo-3-(penta-2,4-di… 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 148 °C (298.4 °F) range, midpoint shown, at 0.0005 mmHg (reduced pressure) HSDB
170 °C (338 °F) decomposes, at 0.1 mmHg (reduced pressure) HSDB
Density 1.5192 g/cm³ at 18 °C HSDB
Solubility Soluble in kerosene, ethylene dichloride, nitromethane. HSDB
Soluble in ethanol, ethyl ether, carbon tetrachloride, petroleum ether HSDB
In water, 0.2 mg/L (temperature not specified) HSDB
Vapor pressure 0.0000203 mmHg DOE PAC
0.0000203 mmHg at 25 °C HSDB

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

04 · Handling and storage

Storing and handling 2-methyl-4-oxo-3-(penta-2,4-di…

Storage conditions

Should be refrigerated and stored in darkness.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

... Incompatible with lime and ordinary soaps because acids & alkalies speed up processes of hydrolysis. /Pyrethrins/

Source: Hazardous Substances Data Bank (HSDB)

Planning storage for a mix of chemicals? Check 2-methyl-4-oxo-3-(penta-2… in the storage compatibility matrix →

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