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)]]-3-(3-methoxy-2-methyl-3-oxoprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate

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

CAS 121-29-9 C22H28O5 372.5 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)]]-3-(3-methoxy-2-methyl-3-oxoprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate is a viscous liquid. Its molecular formula is C22H28O5 and its molecular weight is 372.5 g/mol. It is soluble in water.

Under the GHS it carries the signal word Warning.

02 · Identifiers

2-methyl-4-oxo-3-(penta-2,4-di… identifiers and molecular data

2-methyl-4-oxo-3-(penta-2,4-di… CAS number and EC number

CAS number121-29-9
EC number204-462-6
Index number (CLP Annex VI)613-024-00-7

2-methyl-4-oxo-3-(penta-2,4-di… molecular formula and molecular weight

Molecular formulaC22H28O5
Molecular weight372.5 g/mol

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

  • pyrethrin II

03 · GHS classification

2-methyl-4-oxo-3-(penta-2,4-di… hazard classification

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

2-methyl-4-oxo-3-(penta-2,4-di… pictograms and signal word

Signal wordWarning

2-methyl-4-oxo-3-(penta-2,4-di… hazard class and category

GHS hazard classes 2-methyl-4-oxo-3-(penta-2… falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 4 H302 GHS07
Acute toxicity - dermal GHS chapter 3.1 Category 4 H312 GHS07
Acute toxicity - inhalation GHS chapter 3.1 Category 4 H332 GHS07
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

2-methyl-4-oxo-3-(penta-2,4-di… hazard statements (H-codes)

Hazard statements assigned to 2-methyl-4-oxo-3-(penta-2…
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.

This page lists only the codes assigned to 2-methyl-4-oxo-3-(penta-2…. 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-methyl-4-oxo-3-(penta-2…

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-methyl-4-oxo-3-(pent… 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-methyl-4-oxo-3-(penta-2,4-di… precautionary statements

CLP Annex VI assigns 13 precautionary statements to 2-methyl-4-oxo-3-(penta-2…. 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

2-methyl-4-oxo-3-(penta-2,4-di… 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 2-метил-4-оксо-3-(пента-2,4-диенил)циклопент-2-енилов [1 R - [1α[ S *( Z )](3β)]]-3-(2-метил-3-метокси-3-оксопроп-1-енил)-2,2-диметилциклопропанкарбоксилат пиретрин II
Spanish español [1 R -[1α[ S *( Z )](3β)]]-3-(3-Metoxi-2-metil-3-oxoprop-1-enil)-2,2-dimetilciclopropanocar boxilato de 2-metil-4-oxo-3-(penta-2,4-dienil)ciclopent-2-enilo piretrina II
Czech čeština [2-methyl-4-oxo-3-(( Z )-penta-2,4-dien-1-yl)cyklopent-2-en-1-yl]-3-[2-(methoxykarbonyl)prop-1-en-1-yl]-2,2-dimethylcyklopropan-1-karboxylát pyrethrin II
Danish dansk 2-methyl-4-oxo-3-(penta-2,4-dienyl)cyclopent-2-enyl[1 R -[1α[ S *( Z )](3β)]]-3-(3-methoxy-2-methyl-3-oxoprop-1-enyl)-2,2-dimethylcyclopropancarboxylat pyrethrin II
German Deutsch 2-Methyl-4-oxo-3-(penta-2,4-dienyl)cyclopent-2-enyl[1 R -[1α[ S *( Z )](3β)]]-3-(3-methoxy-2-methyl-3-oxoprop-1-enyl)-2,2-dimethylcyclopropancarboxylat Pyrethrin II
Estonian eesti 2-metüül-4-okso-3-(penta-2,4-dienüül)tsüklopent-2-enüül-[1 R -[1α[ S *( Z )](3β)]]-3-(3-metoksü-2-metüül-3-oksoprop-1-enüül)-2,2-dimetüültsüklopropaankarboksülaat püretriin II
Greek ελληνικά 2-μεθυλ-4-οξο-3-(πεντα-2,4-διενυλο)κυκλοπεντ-2-ενυλο[1 R - [1α[ S *( Z )](3β)]]-3-(3-μεθοξυ-2-μεθυλ-3-οξοπροπ-1-ενυλο)-2,2-διμεθυλοκυκλοπροπανοκαρβοξυλικό πυρεθρίνη ΙΙ
English English 2-methyl-4-oxo-3-(penta-2,4- dienyl)cyclopent-2-enyl[1 R - [1α[ S *( Z )](3β)]]-3-(3-methoxy-2-methyl-3-oxoprop-1-enyl)-2,2- dimethylcyclopropanecar boxylate pyrethrin II
French français [1 R -[1α[ S *( Z )](3β)]]-3-(3-méthoxy-2-méthyl-3-oxoprop-1-ényl)-2,2-diméthylcyclopropanecarboxylate de 2-méthyl-4-oxo-3-(penta-2,4-diényl)cyclopent-2-ényle pyréthrine II
Croatian hrvatski 2-metil-4-okso-3-(penta-2,4-dienil)ciklopent-2-enil[1 R -[1α[ S *( Z )](3β)]]-3-(3-metoksi-2-metil-3-oksoprop-1-enil)-2,2-dimetilciklopropankarboksilat piretrin II
Italian italiano [1 R -[1α[ S *( Z )](3β)]]-3-(3-metossi-2-metil-3-ossoprop-1-enil)-2,2-dimetilciclopropanocarbossilato di 2-metil-4-osso-3-(penta-2,4-dienil)ciclopent-2-enile piretrina II
Latvian latviešu 2-metil-4-okso-3-(penta-2,4-dienil)ciklopent-2-enil[1 R - [1α[ S *( Z )](3β)]]-3-(3-metoksi-2-metil-3-oksoprop-1-enil)-2,2-dimetilciklopropānkarboksilāts piretrīns II
Lithuanian lietuvių 2-metil-4-okso-3-(penta-2,4-dienil)ciklopent-2-enil[1 R -[1α[ S *( Z )](3β)]]-3-(3-metoksi-2-metil--3-oksoprop-1-enil)-2,2-dimetilciklopropankarboksilatas piretrinas II
Hungarian magyar 2-metil-4-oxo-3-(penta-2,4-dienil)ciklopent-2-enil[1R-[1α[S*(Z)],3β]]-3-(3-metoxi-2-metil-3-oxoprop-1-enil)-2,2-dimetilciklopropán-karboxilát piretrin II
Maltese Malti 2-metil-4-osso-3-(penta-2,4- dienol)ċiklopent-2-enil[1 R - [1α[ S *( Z )](3β)]]-3-(3-metossi-2-metil-3-ossoprop-1-enil)-2,2-dimetilċiklopropanekarboksilat pyrethrin II
Dutch Nederlands 2-methyl-4-oxo-3-(penta-2,4-diënyl)cyclopent-2-enyl[1 R -[1α[ S *( Z )](3β)]]-3-(3-methoxy-2-methyl-3-oxoprop-1-enyl)-2,2-dimethylcyclopropaancarboxylaat pyrethrine II
Polish polski 1( E )-(1 R ,3 R )-2,2-dimetylo-3-(3-metoksy-2-metylo-3-oksoprop-1-en-1-ylo)cyklopropanokarboksylan ( Z )-( S )-2-metylo-4-okso-3-(penta-2,4-dien-1-ylo)cyklopent-2-en-1-ylu ( E )-(1 R ,3 R )-2,2-dimetylo-3-metoksykarbonyloprop-1-en-1-ylo)cyklopropanokarboksylan ( Z )-( S )-2-metylo-4-okso-3-(penta-2,4-dien-1-ylo)cyklopent-2-en-1-ylu pyretryna II
Portuguese português [1 R -[1α[ S *( Z )](3β)]]-3-(3-metoxi-2-metil-3-oxoprop-1-enil)-2,2-dimetilciclopropanocarboxilato de 2-metil-4-oxo-3-(penta-2,4-dienil)ciclopent-2-enilo piretrina II
Romanian română [1 R -[1α[ S *( Z )](3β)]]-3-(3-metoxi-2-metil-3-oxo-prop-1-enil)-2,2-dimetilciclopropancarboxilat de 2-metil-4-oxo-3-(penta-2,4-dienil)ciclopent-2-enil piretrine II
Slovak slovenčina O -[2-metyl-4-oxo-3-(penta-2,4-dién-1-yl)cyklopent-2-enyl]-((1 R )-{1α[ S *( Z )](3β)})-3-[2-(metoxykarbonyl)prop-1-én-1-yl]-2,2-dimetylcyklopropánkarboxylát pyretrín II
Slovenian slovenščina 2-metil-4-okso-3-(penta-2,4-dienil)ciklopent-2-enil [1 R -[1α[ S *( Z )](3β)]]-3-(3-metoksi-2-metil-3-oksoprop-1-enil)-2,2-dimetilciklopropankarboksilat piretrin II
Finnish suomi 2-metyyli-4-okso-3-(penta-2,4-dienyyli)syklopent-2-enyyli[1 R -[1α[ S *( Z )](3β)]]-3-(3-metoksi- 2-metyyli-3-oksoprop-1-enyyli)-2,2-dimetyylisyklopropaanikarboksylaatti pyretriini II
Swedish svenska 2-metyl-4-oxo-3-(penta-2,4-dienyl)cyklopent-2-enyl[1 R -[1α[ S *( Z )](3β)]]-3-(3-metoxi-2-metyl-3-oxoprop-1-enyl)-2,2-dimetylcyklopropankarboxylat pyretrin II

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-methyl-4-oxo-3-(penta-2,4-di… GHS label elements

Everything CLP Annex VI fixes for 2-methyl-4-oxo-3-(penta-2…, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS07 Exclamation mark pictogramGHS09 Environment pictogram

Warning

2-methyl-4-oxo-3-(penta-2,4-di…

  • Harmful if inhaled.
  • Harmful in contact with skin.
  • Harmful if swallowed.
  • Very toxic to aquatic life.
  • Very toxic to aquatic life with long lasting effects.
  • 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:
  • Call a POISON CENTER/doctor/ if you feel unwell.
  • Rinse mouth.
  • 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 2-methyl-4-oxo-3-(penta-2… in the GHS label constructor →

07 · Health hazards

2-methyl-4-oxo-3-(penta-2,4-di… health hazards and exposure limits

2-methyl-4-oxo-3-(penta-2,4-di… carcinogenicity classification

Cancer Classification: Suggestive Evidence of Carcinogenicity but Not Sufficient to Assess Human Carcinogenic Potential /Pyrethrins/

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.

2-methyl-4-oxo-3-(penta-2,4-di… occupational exposure limits

US occupational exposure limits reported for 2-methyl-4-oxo-3-(penta-2…. PEL is enforceable (OSHA), REL is a recommendation (NIOSH), IDLH is the concentration at which escape becomes impossible without injury.
Limit Value Source
IDLH 5000 mg/cu m /Pyrethrum/ Hazardous Substances Data Bank (HSDB)

These are United States values. The European Union sets its own indicative and binding limits, and the figure that applies at a given workplace is the one in the local regulation — not the one shown here.

08 · 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.

2-methyl-4-oxo-3-(penta-2,4-di… boiling point

Property Value Conditions Source
Boiling point 200 °C (392 °F) decomposes, at 0.1 mmHg (reduced pressure) HSDB

2-methyl-4-oxo-3-(penta-2,4-di… solubility

Property Value Conditions Source
Solubility Soluble in ethanol, ether, carbon tetrachloride HSDB
Soluble in petroleum ether (less sol than pyrethrin I), kerosene, ethylene dichloride, nitromethane HSDB
In water, 9.0 mg/L (temperature not specified) HSDB

2-methyl-4-oxo-3-(penta-2,4-di… vapor pressure

Property Value Conditions Source
Vapor pressure 3.98e-7 mmHg at 25 °C HSDB

2-methyl-4-oxo-3-(penta-2,4-di… corrosivity

Property Value Conditions Source
Corrosivity Non-corrosive HSDB

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

09 · Handling and storage

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

2-methyl-4-oxo-3-(penta-2,4-di… storage conditions

Pyrethrins with piperonyl butoxide topical preparations should be stored in well-closed containers at a temperature less than 40 °C, preferably between 15-30 °C. /Pyrethrins/

Source: Hazardous Substances Data Bank (HSDB)

2-methyl-4-oxo-3-(penta-2,4-di… 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 →

10 · Questions

2-methyl-4-oxo-3-(penta-2,4-di… — frequently asked questions

What is the CAS number of 2-methyl-4-oxo-3-(penta-2,4-di…?

The CAS number of 2-methyl-4-oxo-3-(penta-2,4-di… is 121-29-9. Its EC number is 204-462-6.

What is the chemical formula of 2-methyl-4-oxo-3-(penta-2,4-di…?

The molecular formula of 2-methyl-4-oxo-3-(penta-2,4-di… is C22H28O5 and its molecular weight is 372.5 g/mol.

What does a 2-methyl-4-oxo-3-(penta-2,4-di… label have to show?

Under CLP Annex VI the label for 2-methyl-4-oxo-3-(penta-2,4-di… carries the pictograms Exclamation mark and Environment and the signal word is Warning.

Is 2-methyl-4-oxo-3-(penta-2,4-di… flammable?

CLP Annex VI assigns 2-methyl-4-oxo-3-(penta-2,4-di… 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 2-methyl-4-oxo-3-(penta-2,4-di… a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for 2-methyl-4-oxo-3-(penta-2,4-di…. 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-methyl-4-oxo-3-(penta-2,4-di…?

The boiling point reported for 2-methyl-4-oxo-3-(penta-2,4-di… is 200 °C (392 °F), decomposes, at 0.1 mmHg (reduced pressure) (HSDB).

How should 2-methyl-4-oxo-3-(penta-2,4-di… be stored?

Pyrethrins with piperonyl butoxide topical preparations should be stored in well-closed containers at a temperature less than 40 °C, preferably between 15-30 °C. /Pyrethrins/ (Hazardous Substances Data Bank (HSDB))

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