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

3,5,5-trimethylcyclohex-2-enone

3,5,5-trimethylcyclohex-2-enone is a water-white liquid with a peppermint-like odor.

CAS 78-59-1 Warning

01 · Identification

What 3,5,5-trimethylcyclohex-2-enon… is

3,5,5-trimethylcyclohex-2-enone is a water-white liquid with a peppermint-like odor. It boils at 215 °C, melts at -8.1 °C, is soluble in water.

Under the GHS it carries the signal word Warning. It is classed as hazardous Air Pollutants (HAPs).

CAS number78-59-1
EC number201-126-0
Index number606-012-00-8
Chemical class Hazardous Air Pollutants (HAPs)

Other names for 3,5,5-trimethylcyclohex-2-enon…

  • isophorone

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 3,5,5-trimethylcyclohex-2-enon…
CodeHazard statement
H351 Suspected of causing cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H312 Harmful in contact with skin.
H302 Harmful if swallowed.
H335 May cause respiratory irritation.
H319 Causes serious eye irritation.

Precautionary statements: P201, P264, P270, P280, P301, P302, P305, P308, P312, P313, P330, P337, P338, P352

03 · Physical and chemical properties

3,5,5-trimethylcyclohex-2-enon… 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 215.32 °C (419.6 °F) HSDB
215 °C (419 °F) NIOSH
215.22 °C (419.4 °F) at 760 mmHg CAMEO
Melting point -8.1 °C (17.4 °F) HSDB
-8.33 °C (17 °F) NIOSH
-7.78 °C (18 °F) CAMEO
Density 0.92 g/cm³ NIOSH
0.9255 g/cm³ at 20 °C HSDB
0.9227 g/cm³ at 20 °C HSDB
Solubility Soluble in ether, acetone, alcohol HSDB
Has high solvent power for vinyl resins, cellulose esters, ether, and many substances soluble with difficulty in other solvents. HSDB
In water, 12,000 mg/l @ 25 °C. at 25 °C HSDB
Vapor pressure 0.3 mmHg NIOSH
0.2 mmHg at 20 °C CAMEO
0.438 mmHg at 25 °C HSDB
Flash point 84.44 °C (184 °F) HSDB
Autoignition temperature 460 °C (860 °F) HSDB
462.22 °C (864 °F) CAMEO
Lower explosive limit (LEL) 0.8 % by volume HSDB
Upper explosive limit (UEL) 3.8 % by volume HSDB
Vapor density 4.77 (air = 1) HSDB
4.8 (air = 1) ICSC
Odor threshold Odor detection in air= 2.00 ppm. Purity not specified. HSDB
Odor recognition in air= 5.40 ppm. Purity not specified. HSDB
1 mg/cu m (odor low); 50 mg/cu m (odor high) HSDB

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

04 · Handling and storage

Storing and handling 3,5,5-trimethylcyclohex-2-enon…

Storage conditions

store in a cool, dry, well-ventilated location. Outside or detached storage is preferred. Separate from oxidizing materials.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Incompatible with strong oxidizers

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

Ketones, such as ISOPHORONE, are reactive with many acids and bases liberating heat and flammable gases (e.g., H2). The amount of heat may be sufficient to start a fire in the unreacted portion of the ketone. Ketones react with reducing agents such as hydrides, alkali metals, and nitrides to produce flammable gas (H2) and heat. Ketones are incompatible with isocyanates, aldehydes, cyanides, peroxides, and anhydrides. They react violently with aldehydes, HNO3, HNO3 + H2O2, and HClO4. Forms explosive peroxides

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check 3,5,5-trimethylcyclohex-2… in the storage compatibility matrix →

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