Basic information
- Standard SMILES
CC(C)C=O- InChIKey
AMIMRNSIRUDHCM-UHFFFAOYSA-N- Molecular formula
- C4H8O
- Average molar mass
- 72.11 g/mol
- Monoisotopic mass
- 72.05751488
Overview
Isobutyl aldehyde appears as a clear colorless liquid with a pungent odor. Flash point of -40 °F. Less dense than water and insoluble in water. Hence floats on water. Vapors are heavier than air. Used to make other chemicals.
Names & identifiers
- Preferred name
- Isobutyraldehyde
- IUPAC
- 2-methylpropanal
- English name
- 2-Methylpropanal
- Molecular formula
- C4H8O
- Molecular weight
- 72.10572
Names & synonyms
Show more names
Database identifiers
- CAS
78-84-2- PubChem CID
- 6561
- DTXSID
DTXSID9021635- ChEMBL
CHEMBL1404017- ChEBI
CHEBI:48943- UNII
- C42E28168L
- EC Number
- 201-149-6
- Nikkaji
- J1.483D
Properties
Computed structural properties
- XLogP
- 0.8
- Topological polar surface area
- 17.1 Ų
- Hydrogen bond donors
- 0
- Hydrogen bond acceptors
- 1
- Rotatable bonds
- 1
- Heavy atoms
- 5
- Formal charge
- 0
- Complexity
- 30.6
Experimental & physicochemical properties
Chemical Classes
Other Classes -> Aldehydes
Flammable agents - 3rd degree
LogP
0.740
1.2
0.4
Odor
EXTREMELY SHARP
Pungent odor
Density
0.791 at 68 °F (USCG, 1999) - Less dense than water; will float
0.7938 @ 20 °C/4 °C
0.8 g/cm³
Relative density of the vapour/air-mixture at 20 °C (air = 1): 1.2
0.783-0.788
0.7938 @ 20°C
Viscosity
0.5382 cP @ 28.2 °C
0.7 mm²/s at 28 °C
Solubility
less than 1 mg/mL at 66 °F (NTP, 1992)
Miscible in ethanol, ether, carbon disulfide, acetone, benzene, toluene, and chloroform.
Slightly soluble in carbon tetrachloride
In water, 89,000 mg/l @ 25 °C.
89 mg/mL at 25 °C
Solubility in water, g/100ml at 20 °C: 6.7 (moderate)
Physicochemical properties
- Melting point
- -65.9 °C · -65.9 °C
- Boiling point
- 64 °C · 64 °C
- Density
- 0.7938 g/cm3 · 0.7938 g/cm3
- Symbol(GHS)
- 2 · GHS02,GHS07
- Signal word
- Danger
- Hazard statements
- 225 · H225-H319
- Precautionary statements
- 210 · P210-P233-P240-P241-P242-P305+P351+P338
- RIDADR
- 2045 · UN 2045
- HazardClass
- 3 · 3
- PackingGroup
- II
Safety & regulation
GHS classification
GHS Classification
Danger
H225 (100%): Highly Flammable liquid and vapor [Danger Flammable liquids]
P210, P233, P240, P241, P242, P243, P264+P265, P280, P303+P361+P353, P305+P351+P338, P337+P317, P370+P378, P403+P235, and P501 (click each P-code to see the statement)
Aggregated GHS information provided per 4104 reports by companies from 15 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.
Danger
H225: Highly Flammable liquid and vapor [Danger Flammable liquids]
Hazard information
Regulatory Information
Chemical: Propanal, 2-methyl-
Regulation (EC) No 1831/2003 (amended)
Propanal, 2-methyl- is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of Propanal, 2-methyl- are required to report information about their production and use of this chemical to the EPA under the Toxic Substances Control Act (TSCA). (40 eCFR Part 711)
Status: Active Update: 17-10-2022 https://echa.europa.eu/registration-dossier/-/registered-dossier/14300
Propanal, 2-methyl-: HSNO Approval: HSR001256 Approved with controls
The New Jersey Worker and Community Right to Know Act requires public and private employers to provide information about hazardous substances at their workplaces. (N.J.S.A. 34:5A-1 et. seq.)
Fire Hazards
Behavior in Fire: Vapors are heavier than air and may travel considerable distance to a source of ignition and flash back. Fires are difficult to control due to ease of reignition. (USCG, 1999)
· HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.
· HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.
Highly flammable. Gives off irritating or toxic fumes (or gases) in a fire. Vapour/air mixtures are explosive.
Health Hazards
Vapor is irritating to the eyes and mucous membranes. (USCG, 1999)
· May cause toxic effects if inhaled or absorbed through skin.
· May cause toxic effects if inhaled or absorbed through skin.
Hazards Summary
A corrosive substance that can cause pulmonary edema; Can cause skin burns; Can cause severe burns to eyes; [ICSC] Inhalation of high concentrations can cause CNS depression; [HSDB] An irritant; [MSDSonline] No irritation in 15 volunteers exposed to 210 ppm, but two became nauseated; [AIHA]
DOT ID and Guide
2045 130
2045 130
FDA Requirements
Isobutyraldehyde is a food additive permitted for direct addition to food for human consumption as a synthetic flavoring substance and adjuvant in accordance with the following conditions: a) they are used in the minimum quantity required to produce their intended effect, and otherwise in accordance with all the principles of good manufacturing practice, and 2) they consist of one or more of the following, used alone or in combination with flavoring substances and adjuvants generally recognized as safe in food, prior-sanctioned for such use, or regulated by an appropriate section in this part.
Special Reports
Toxicology & Carcinogenesis Studies of Isobutyraldehyde in F344/N Rats and B6C3F1 Mice. Technical Report Series No. 472 (1999) NIH Publication No. 99-3962 U.S. Department of Health and Human Services, National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709
TSCA Requirements
Section 8(a) of TSCA requires manufacturers of this chemical substance to report preliminary assessment information concerned with production, use, and exposure to EPA as cited in the preamble in 51 FR 41329.
Pursuant to section 8(d) of TSCA, EPA promulgated a model Health and Safety Data Reporting Rule. The section 8(d) model rule requires manufacturers, importers, and processors of listed chemical substances and mixtures to submit to EPA copies and lists of unpublished health and safety studies. 2-Methylpropanal is included on this list.
Safety & protection
Fire Fighting
Excerpt from ERG Guide 130 [Flammable Liquids (Water-Immiscible / Noxious)]:
Use powder, foam, carbon dioxide. In case of fire: keep drums, etc., cool by spraying with water.
First Aid Measures
Fresh air, rest. Refer for medical attention.
Rinse skin with plenty of water or shower. Remove contaminated clothes. Refer for medical attention .
First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.
Rinse mouth. Do NOT induce vomiting. Give one or two glasses of water to drink. Refer for medical attention .
Accidental Release Measures
· CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper not available or no answer, refer to appropriate telephone number listed on the inside back cover.
· ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area.
· CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper not available or no answer, refer to appropriate telephone number listed on the inside back cover.
· ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area.
First Aid
EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.
General First Aid:
General First Aid:
Exposure Control and Personal Protection
· Wear positive pressure self-contained breathing apparatus (SCBA).
· Wear positive pressure self-contained breathing apparatus (SCBA).
Fire Fighting Procedures
Foam, dry chemical or carbon dioxide.
WEAR GOGGLES & SELF-CONTAINED BREATHING APPARATUS. ... COOL EXPOSED CONTAINERS WITH WATER.
Storage Conditions
MATERIALS WHICH ARE TOXIC AS STORED OR WHICH CAN DECOMPOSE INTO TOXIC COMPONENTS ... SHOULD BE STORED IN A COOL WELL VENTILATED PLACE, OUT OF THE DIRECT RAYS OF THE SUN, AWAY FROM AREAS OF HIGH FIRE HAZARD, AND SHOULD BE PERIODICALLY INSPECTED. INCOMPATIBLE MATERIALS SHOULD BE ISOLATED ... .
Disposal Methods
SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.
(1) Absorb on vermiculite and burn in open incinerator. (2) Dissolve in flammable solvent and spray in incinerator with after burner.
Spillage Disposal
Evacuate danger area! Consult an expert! Remove all ignition sources. Personal protection: protective clothing, protective gloves, safety goggles and filter respirator for organic vapours of low boiling point adapted to the airborne concentration of the substance. Do NOT let this chemical enter the environment. Do NOT wash away into sewer. Collect leaking liquid in sealable containers. Cover the spilled material with inert absorbent. Then store and dispose of according to local regulations.
Toxicology
Environmental Fate
TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 8(SRC), determined from a water solubility of 8.9X10+4(2) and a regression-derived equation(3), indicates that isobutyraldehyde is expected to have very high mobility in soil(SRC). Volatilization of isobutyraldehyde from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 1.8X10-4 atm-cu m/mole(SRC), derived from its vapor pressure, 173 mm Hg(4), and its water solubility(2). The potential for volatilization of isobutyraldehyde from dry soil surfaces may exist(SRC) based upon a its vapor pressure(4). Biodegradation is expected to be the major environmental fate process for isobutyraldehyde in soil since it was found to readily biodegrade in water(5).
AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 8(SRC), determined from a water solubility of 8.9X10+4(2) and a regression-derived equation(3), indicates that isobutyraldehyde is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon an estimated Henry's Law constant of 1.8X10-4 atm-cu m/mole(SRC), derived from its vapor pressure, 173 mm Hg(4), and its water solubility(2). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 3.6 hrs and 4.6 days, respectively(SRC). According to a classification scheme(5), an estimated BCF of 1(SRC), from its water solubility(2) and a regression-derived equation(3), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Isobutyraldehyde, present at 100 mg/l, reached 81% of its theoretical BOD in 2 weeks using an activated sludge inoculum at 30 mg/l and the Japanese MITI test(6).
ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), isobutyraldehyde, which has a vapor pressure of 173 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere(SRC). Vapor-phase isobutyraldehyde is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 14.6 hours(SRC), calculated from its rate constant of 2.6X10-11 cu cm/molecule-sec at 25 °C(3). Based upon direct photolysis measurements, the direct photolysis rate constants of isobutyraldehyde at solar zenith angles of 30 and 58 deg were determined to be 7.6X10-5 and 5.9X10-5 /sec(4), respectively, which correspond to respective half-lives of 2.5 and 3.3 hr(SRC).
Food Survey Values
Isobutyraldehyde has been qualitatively detected as a volatile constituent of coffee(1), fried bacon(2), roasted filbert nuts(3), cooked meats(4), and chickpeas(5). Isobutyraldehyde concns of 27-140 ppb were detected in dried samples of lima beans, common beans, mung beans, soybeans, split peas, and lentils(6). Isobutyraldehyde has been qualitatively detected in peanut butter(7), cheddar cheese(8), and bread(9). Isobutyraldehyde was qualitatively detected in whole and ground grain samples(10).
Signs and Symptoms
Sore throat. Cough. Burning sensation. Headache. Dizziness. Nausea. Vomiting.
Redness.
Pain. Redness.
Abdominal cramps. Aspiration hazard! Further see Inhalation.
Ongoing Test Status
The following link will take the user to the National Toxicology Program (NTP) Test Agent Search Results page, which tabulates all of the "Standard Toxicology & Carcinogenesis Studies", "Developmental Studies", and "Genetic Toxicity Studies" performed with this chemical. Clicking on the "Testing Status" link will take the user to the status (i.e., in review, in progress, in preparation, on test, completed, etc.) and results of all the studies that the NTP has done on this chemical. [http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=ntpsearch.searchresults&searchterm=78-84-2]
Effluent Concentrations
Isobutyraldehyde emission factors ranging from 2.6 to 79.5 mg/kg were detected in the flue gas of cookstoves(1). Isobutyraldehyde's emission rate from hamburger meat charbroiling over a natural gas fired grill was measured and found to be 373,000 ug/kg(2).
An isobutyraldehyde concn of 0.13 ppm was detected in an automobile exhaust sample(1); isobutyraldehyde was qualitatively detected in wood smoke emissions(1). Isobutyraldehyde has been detected in volatile emissions from Northern white cedar trees(2). Monitoring of automobile exhaust from four vehicles equipped in low nitrogen oxide catalytic converters, detected mean isobutyraldehyde emission rates of 0.14-1.57 mg/km(3).
Soil Adsorption/Mobility
The Koc of isobutyraldehyde is estimated as 8(SRC), using a water solubility of 8.9X10+4(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that isobutyraldehyde is expected to have very high mobility in soil(SRC).
Natural Pollution Sources
REPORTED FOUND IN APPLE & CURRANT AROMAS & IN ESSENTIAL OILS FROM TOBACCO LEAVES & TEA LEAVES; ALSO IN THE ESSENTIAL OILS OF: PINUS JEFFREYI MURR LEAVES, CITRUS AURANTIUM LEAVES, & DATURA STRAMONIUM.
Similar to other saturated aldehydes, isobutyraldehyde occurs naturally in foods(1); it is also emitted into the atmosphere by plants(1).
Regulatory information
FDA Requirements
Isobutyraldehyde is a food additive permitted for direct addition to food for human consumption as a synthetic flavoring substance and adjuvant in accordance with the following conditions: a) they are used in the minimum quantity required to produce their intended effect, and otherwise in accordance with all the principles of good manufacturing practice, and 2) they consist of one or more of the following, used alone or in combination with flavoring substances and adjuvants generally recognized as safe in food, prior-sanctioned for such use, or regulated by an appropriate section in this part.
TSCA Requirements
Section 8(a) of TSCA requires manufacturers of this chemical substance to report preliminary assessment information concerned with production, use, and exposure to EPA as cited in the preamble in 51 FR 41329.
Pursuant to section 8(d) of TSCA, EPA promulgated a model Health and Safety Data Reporting Rule. The section 8(d) model rule requires manufacturers, importers, and processors of listed chemical substances and mixtures to submit to EPA copies and lists of unpublished health and safety studies. 2-Methylpropanal is included on this list.
Atmospheric Standards
This action promulgates standards of performance for equipment leaks of Volatile Organic Compounds (VOC) in the Synthetic Organic Chemical Manufacturing Industry (SOCMI). The intended effect of these standards is to require all newly constructed, modified, and reconstructed SOCMI process units to use the best demonstrated system of continuous emission reduction for equipment leaks of VOC, considering costs, non air quality health and environmental impact and energy requirements. Isobutyraldehyde is produced, as an intermediate or a final product, by process units covered under this subpart.
Safety data
- ridadr
- UN 2045
- Signal word
- Danger
- Symbol(GHS)
- GHS02,GHS07
- hazard_class
- 3
- packing_group
- II
- Hazard statements
- H225-H319
- Precautionary statements
- P210-P233-P240-P241-P242-P305+P351+P338
Chemistry & industry
Pharmacology
Uses & manufacturing
Uses
Used in organic synthesis (pantothenic acid, valine, leucine, cellulose esters, perfumes, flavors, plasticizers, resins, and gasoline additives); [Merck Index] Used as a chemical intermediate; [Hawley] An FDA-approved flavoring agent and it occurs naturally in foods; [AIHA]
Synthesis of pantothenic acid, cellulose esters, perfumes, flavors, and gasoline additives.
ITS DERIVATIVES ARE USED IN MEDICINES & IN MOLD INHIBITORS & REPELLENTS
CHEM INT FOR ISOBUTYL ALCOHOL FOR RESINS & PLASTICIZERS & FOR ISOBUTYRIC ACID & ITS ESTERS, FOR AMINO ACIDS (VALINE, LEUCINE) & FOR PANTOTHENIC ACID IN CHICKEN FEED, FOR ISOBUTYRALDEHYDE OXIME & FOR 2,2,4-TRIMETHYL-1,3-PENTANEDIOL & DERIVATIVES, FOR NEOPENTYL GLYCOL & DERIVATIVES & FOR TRIMETHYL PENTANOL & DERIVATIVES
Intermediate for rubber antioxidants and accelerators for neopentyl glycol; synthesis of amino acids.
U.S. Production
2023: 500,000,000 - <1,000,000,000 lb
(1974) 1.73X10+11 G
(1975) GREATER THAN 4.54X10+5 G
(1991) 4.47X10+8 lbs
Methods of Manufacturing
REACTION OF PROPYLENE, CARBON MONOXIDE, AND HYDROGEN IN THE PRESENCE OF A COBALT CATALYST (OXO PROCESS), FOLLOWED BY SEPARATION OF ISOMERS BY DISTILLATION
Mfr by oxo process from propylene, carbon monoxide, and hydrogen @ 130-160 °C and 1500-3000 psi in presence of cobalt catalyst: Roelen, US patent 2,327,066 (1943); also prepd by air oxidn of isobutyl alcohol: Fossek, Monatsh 2, 614 (1881); Lipp, Ann 205, 2 (1880).
BY OXIDATION OF ISOBUTYL ALCOHOL WITH POTASSIUM DICHROMATE & CONCENTRATED SULFURIC ACID. COTTET ET AL, BULL SOC CHIM FR, 12, 4499, 1967.
Propylene + synthesis gas (hydroformylation; coproduced with n-butyraldehyde)
Use Classification
Fragrance Ingredients
Flavouring Agent -> FLAVOURING_AGENT -> JECFA Functional Classes
Flavoring Agents -> JECFA Flavorings Index
General Manufacturing Information
Plastics Material and Resin Manufacturing
Propanal, 2-methyl-: ACTIVE
FEMA NUMBER 2220
ISOBUTYRALDEHYDE & ITS COGENERS OCCUR IN A WIDE VARIETY OF FEEDSTUFFS, WHERE THEY MAY SERVE AS INDICATORS FOR THE AVAILABILITY OF THE INDISPENSABLE AMINO ACIDS VALINE, LEUCINE, & ISOLEUCINE.
Suppliers50 total
Related reactions
Linked notes
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