Acetylacetone

1Identification

Name

Acetylacetone

IUPAC name

pentane-2,4-dione

CAS number

123-54-6

EC number

204-634-0

Molecular formula

C5H8O2

Molecular weight

100.12 g/mol

InChIKey

YRKCREAYFQTBPV-UHFFFAOYSA-N

SMILES

CC(=O)CC(=O)C

PubChem CID

31261

Synonyms

Acetylacetone, 2,4-Pentanedione, Pentane-2,4-dione, 2,4-Dioxopentane, Acetoacetone, Diacetylmethane, ACAC, Pentanedione, ACETYL ACETONE, Pentan-2,4-dione, Pentanedione-2,4, Acetyl 2-propanone, Acetone, acetyl-, Hacac

Recommended uses

• Used as a chemical intermediate, solvent, metal chelating agent, lubricant additive, and pesticide; [Hawley] Used as a metal chelator, lubricant additive, corrosion inhibitor, polyolefin modifier, and intermediate; [ACGIH]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
• Painting (Solvents) [Category: Paint]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
• Forms organometallic complexes which are used as gasoline additives, lubricant additives, driers for varnishes and printer's inks ... .
  Hazardous Substances Data Bank (HSDB)
• Stabilizing agent Catalyst Not Known or Reasonably Ascertainable Diluent Hardener Drier Intermediate Surface modifier Laboratory chemicals Solvent Dispersing agent Other Chemical reaction regulator
  EPA Chemical Data Reporting (CDR)
• Other Solvent Chemical reaction regulator Diluent Corrosion inhibitor
  EPA Chemical Data Reporting (CDR)

Description

• Pentane-2,4-dione appears as a colorless or yellow colored liquid. Less dense than water. Vapors are heavier than air. Used as a solvent in paints and varnishes.
  CAMEO Chemicals
• Acetylacetone is a beta-diketone that is pentane in which the hydrogens at positions 2 and 4 are replaced by oxo groups. It is a conjugate acid of an acetylacetonate.
  ChEBI
• acetylacetone has been reported in Nicotiana tabacum, Mangifera indica, and Geijera parviflora with data available.
  LOTUS - the natural products occurrence database

2Hazard identification

Signal word

Warning

Pictograms

GHS02, GHS07

Classification source

Regulation (EC) No 1272/2008 of the European Parliament and of the Council

Precautionary statements

Other reported classifications

6 classification records exist across sources. Differences usually reflect purity, physical form or impurities.

NFPA 704 rating

• 2 - Materials that, under emergency conditions, can cause temporary incapacitation or residual injury.
  Hazardous Substances Data Bank (HSDB)
• 3 - Liquids and solids that can be ignited under almost all ambient temperature conditions. Materials produce hazardous atmospheres with air under almost all ambient temperatures or, though unaffected by ambient temperatures, are readily ignited under almost all conditions.
  Hazardous Substances Data Bank (HSDB)
• 0 - Materials that in themselves are normally stable, even under fire conditions.
  Hazardous Substances Data Bank (HSDB)

Health hazards

• Inhalation causes dizziness, headache, nausea, vomiting and loss of consciousness. Contact with liquid irritates eyes. (USCG, 1999)
  CAMEO Chemicals
• · TOXIC; may be fatal if inhaled, ingested or absorbed through skin. · Inhalation or contact with some of these materials will irritate or burn skin and eyes. · Methyl chloroacetate (UN2295) is an eye irritant/lachrymator (causes flow of tears). · Fire will produce irritating, corrosive and/or toxic gases. · Vapors may cause dizziness or asphyxiation, especially when in closed or confined areas. · Runoff from fire control or dilution water may cause environmental contamination.
  Emergency Response Guidebook (ERG)

Fire hazards

• Behavior in Fire: Vapor is heavier than air and may travel to a source of ignition and flash back. (USCG, 1999)
  CAMEO Chemicals
• · HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. CAUTION: Methanol (UN1230) will burn with an invisible flame. Use an alternate method of detection (thermal camera, broom handle, etc.) · Vapors may form explosive mixtures with air. · Vapors may travel to source of ignition and flash back. · Most vapors are heavier than air. They will spread along the ground and collect in low or confined areas (sewers, basements, tanks, etc.). · Vapor explosion and poison hazard indoors, outdoors or in sewers. · Those substances designated with a (P) may polymerize explosively when heated or involved in a fire. · Runoff to sewer may create fire or explosion hazard.
  Emergency Response Guidebook (ERG)
• Flammable. Above 34 °C explosive vapour/air mixtures may be formed.
  ILO-WHO International Chemical Safety Cards (ICSCs)

Hazards summary

• Causes narcosis with an oral LD50 of 575-1000 mg/kg in rats; Rats inhaling 650 ppm six hours five times weekly for 14 weeks show degenerative changes of the brain and thymus; No neurotoxicity at 307 ppm; [ACGIH] Inhalation of high concentrations causes narcosis; [CHEMINFO MSDS]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

3Composition / information on ingredients

This page describes the pure substance. Commercial products may be solutions or mixtures. Check Section 3 of your supplier's SDS for concentrations and other ingredients.

4First-aid measures

• INHALATION: remove to fresh air; if victim is not breathing, give artificial respiration and then oxygen; call a physician. EYES or SKIN: flush with water. (USCG, 1999)
  CAMEO Chemicals
• General First Aid: · Call 911 or emergency medical service. · Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination. · Move victim to fresh air if it can be done safely. · Administer oxygen if breathing is difficult. · If victim is not breathing: -- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance. -- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped with a one-way valve or other device).
  Emergency Response Guidebook (ERG)

Symptoms of exposure

• Incoordination. Dizziness. Drowsiness. Headache. Laboured breathing. Nausea. Vomiting. Ataxia
  ILO-WHO International Chemical Safety Cards (ICSCs)
• MAY BE ABSORBED! Redness.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Redness. Pain.
  ILO-WHO International Chemical Safety Cards (ICSCs)

5Fire-fighting measures

• Suitable extinguishing media: Dry powder, dry sand. Unsuitable extinguishing media: Do NOT use water jet.
  Hazardous Substances Data Bank (HSDB)
• Advice for firefighters: Wear self-contained breathing apparatus for firefighting if necessary.
  Hazardous Substances Data Bank (HSDB)
• Use water spray to cool unopened containers.
  Hazardous Substances Data Bank (HSDB)

Hazardous combustion products

• Poisonous gases are produced in fire.
  Hazardous Substances Data Bank (HSDB)

6Accidental release measures

Isolation and evacuation

• Excerpt from ERG Guide 131 [Flammable Liquids - Toxic]: IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area for at least 50 meters (150 feet) in all directions. SPILL: Increase the immediate precautionary measure distance, in the downwind direction, as necessary. FIRE: If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2024)
  CAMEO Chemicals
• Immediate precautionary measure · Isolate spill or leak area for at least 50 meters (150 feet) in all directions. Spill · For highlighted materials: see Table 1 - Initial Isolation and Protective Action Distances. · For non-highlighted materials: increase the immediate precautionary measure distance, in the downwind direction, as necessary. Fire · If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions.
  Emergency Response Guidebook (ERG)

Spill cleanup

• Personal protection: filter respirator for organic gases and vapours adapted to the airborne concentration of the substance. Do NOT let this chemical enter the environment. Ventilation. Collect leaking liquid in sealable containers. Wash away remainder with plenty of water.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Wear respiratory protection. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Remove all sources of ignition. Evacuate personnel to safe areas. Beware of vapors accumulating to form explosive concentrations. Vapors can accumulate in low areas. Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Methods and materials for containment and cleaning up: Contain spillage, and then collect with non-combustible absorbent material, (e.g.
  Hazardous Substances Data Bank (HSDB)
• Evacuate and restrict persons not wearing protective equipment from area of spill or leak until cleanup is complete. Remove all ignition sources. Establish forced ventilation to keep levels below explosive limit. Absorb liquids in vermiculite, dry sand, earth, peat, carbon, or a similar material and deposit in sealed containers. Keep this chemical out of a confined space, such as a sewer, because of the possibility of an explosion, unless the sewer is designed to prevent the buildup of explosive concentrations. It may be necessary to contain and dispose of this chemical as a hazardous waste.
  Hazardous Substances Data Bank (HSDB)

7Handling and storage

• Fireproof. Separated from strong oxidants. Keep in the dark.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. Storage class (TRGS 510): 3: Flammable liquids.
  Hazardous Substances Data Bank (HSDB)
• Store in a flammable liquid storage area or approved cabinet away from ignition sources and corrosive and reactive materials. Prior to working with this chemical you should be trained on its proper handling and storage. Before entering confined space where this chemical may be present, check to make sure that an explosive concentration is not a danger. Store in stainless steel containers away from oxidizers, reducing agents, bases. Where possible, automatically pump liquid from drums or other storage containers to process containers. Sources of ignition, such as smoking and open flames, are prohibited where this chemical is handled, used, or stored.
  Hazardous Substances Data Bank (HSDB)

8Exposure controls / personal protection

Personal protective equipment

• Safety glasses; eye bath and safety shower; air-supplied mask for concentrations above 2% (USCG, 1999)
  CAMEO Chemicals
• Eye/face protection: Face shield and safety glasses. Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU).
  Hazardous Substances Data Bank (HSDB)
• Skin protection: Handle with gloves.
  Hazardous Substances Data Bank (HSDB)
• Body Protection: Complete suit protecting against chemicals. Flame retardant antistatic protective clothing. The type of protective equipment must be selected according to the concentration and amount of the dangerous substance at the specific workplace.
  Hazardous Substances Data Bank (HSDB)

9Physical and chemical properties

10Stability and reactivity

Reactivity

• Ketones, such as PENTANE-2,4-DIONE, 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. May dissolve plastics (USCG, 1999).
  CAMEO Chemicals
• Highly flammable. Soluble in water.
  CAMEO Chemicals

Incompatible materials and hazardous reactions

• Incompatible materials: Strong oxidizing agents, reducing agents, strong bases, metals.
  Hazardous Substances Data Bank (HSDB)
• Incompatibilities: Oxidizing material, bases, reducing agents, halogens, aliphatic amines, alkanolamines, organic acids, isocyanates. Light may cause polymerization.
  Hazardous Substances Data Bank (HSDB)

Chemical stability

• Stable under recommended storage conditions.
  Hazardous Substances Data Bank (HSDB)

11Toxicological information

Short-term exposure effects

• The substance is irritating to the eyes, skin and respiratory tract. The substance may cause effects on the nervous system. This may result in tissue lesions.
  ILO-WHO International Chemical Safety Cards (ICSCs)

Long-term exposure effects

• Repeated or prolonged contact may cause skin sensitization. The substance may have effects on the thymus, lungs, central nervous system and nasal passage.
  ILO-WHO International Chemical Safety Cards (ICSCs)

12Ecological information

Not available in the public sources we compile. Check Section 12 of the supplier's SDS.

13Disposal considerations

• SRP: Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.
  Hazardous Substances Data Bank (HSDB)
• SRP: Wastewater from contaminant suppression, cleaning of protective clothing/equipment, or contaminated sites should be contained and evaluated for subject chemical or decomposition product concentrations. Concentrations shall be lower than applicable environmental discharge or disposal criteria. Alternatively, pretreatment and/or discharge to a permitted wastewater treatment facility is acceptable only after review by the governing authority and assurance that "pass through" violations will not occur. Due consideration shall be given to remediation worker exposure (inhalation, dermal and ingestion) as well as fate during treatment, transfer and disposal.
  Hazardous Substances Data Bank (HSDB)
• Product: Contact a licensed professional waste disposal service to dispose of this material. Offer surplus and non-recyclable solutions to a licensed disposal company. Burn in a chemical incinerator equipped with an afterburner and scrubber but exert extra care in igniting as this material is highly flammable; Contaminated packaging: Dispose of as unused product.
  Hazardous Substances Data Bank (HSDB)

14Transport information

UN number: UN 2310

Shipping name

• UN 2310; Pentane-2,4-dione
  Hazardous Substances Data Bank (HSDB)
• IMO 3; Pentane-2,4-dione
  Hazardous Substances Data Bank (HSDB)

DOT hazard class

• Pentane-2,4-dione
  US Code of Federal Regulations, Hazardous Materials, 49 CFR Part 172
• UN2310
  US Code of Federal Regulations, Hazardous Materials, 49 CFR Part 172
• Class 3 Flammable and combustible liquid (49 eCFR § 173.120)
  US Code of Federal Regulations, Hazardous Materials, 49 CFR Part 172

DOT label

• Flammable Liquid Poison
  CAMEO Chemicals

UN classification

• UN Hazard Class: 3; UN Subsidiary Risks: 6.1; UN Pack Group: III
  ILO-WHO International Chemical Safety Cards (ICSCs)

Emergency Response Guidebook

• 2310 131
  Emergency Response Guidebook (ERG)

How DOT hazard classes work →

15Regulatory information

• Section 8(a) of TSCA requires manufacturers of this chemical substance to report preliminary assessment information concerned with production, exposure, and use to EPA as cited in the preamble in 51 FR 41329. Effective date: 9/30/91; Reporting date: 11/27/91.
  Hazardous Substances Data Bank (HSDB)
• 2,4-Pentanedione is an indirect food additive for use only as a component of adhesives.
  Hazardous Substances Data Bank (HSDB)

Overview of SDS regulations (OSHA HazCom, WHMIS, REACH/CLP) →

16Other information

Compiled from PubChem CID 31261 and the sources it aggregates (attributed inline). Data retrieved 2026-10-12. This summary describes the pure substance and is not a supplier SDS.