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CAS 123-51-3

CAS 123-51-3 matches 0 EU annex records across Annex II–VI of Regulation 1223/2009.

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Chemical identity and properties

PubChem 2D chemical structure for CAS 123-51-3
CAS 123-51-3PubChem CID 31260

Isoamyl Alcohol

Isoamylol is an primary alcohol that is butan-1-ol in which a hydrogen at position 3 has been replaced by a methyl group. It has a role as an antifungal agent, a Saccharomyces cerevisiae metabolite and a xenobiotic metabolite. It is a volatile organic compound, a primary alcohol and an alkyl alcohol. It derives from a hydride of an isopentane. — ChEBI

IUPAC name
3-methylbutan-1-ol
Molecular formula
C5H12O
Molecular weight
88.15 g/mol
Exact mass
88.088815002 Da
XLogP3
1.2
Topological polar surface area
20.2 Ų
Hydrogen-bond donors
1
Hydrogen-bond acceptors
1
Covalent units
1
Defined stereocentres
0

Also known as

3-Methyl-1-butanolIsopentyl alcoholIsopentanol3-Methylbutanol1-Butanol, 3-methyl-IsoamylolIsobutylcarbinol2-Methyl-4-butanol
16 more reported names
Isobutyl carbinolIso-amylalkoholISOAMYLALCOHOLAlcool isoamyliqueAmylowy alkoholIsoamyl alkoholAlcool amilicoFermentation amyl alcohol3-Metil-butanoloPrimary isoamyl alcohol3-methyl butanolFEMA No. 2057FEMA Number 2057DEM9NIT1J4NSC-1029NSC-7905
Open full PubChem recordPubChem annotations3D structure image
External database identifiers

Evidence from additional scientific databases

NIH PubChem PUG-View
Exact identifier match31260

Attributed physical-property, hazard, environmental and use annotations.

  • First Aid: Excerpt from NIOSH Pocket Guide for Isoamyl alcohol (primary):; Eye: IRRIGATE IMMEDIATELY - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.; Skin: WATER FLUSH PROMPTLY - If this chemical contacts the skin, flush the contaminated skin with water promptly. If this chemical penetrates the clothing, immediately remove the clothing and flush the skin with water promptly. If irritation persists after washing, get medical attention.; Breathing: RESPIRATORY SUPPORT - If a person breathes large amounts of this chemical, move the exposed person to fresh air at once. If breathing has stopped, perform artificial respiration. Keep the affected person warm and at rest. Get medical attention as soon as possible.; Swallow: MEDICAL ATTENTION IMMEDIATELY - If this chemical has been swallowed, get medical attention immediately. (NIOSH, 2024) Source: CAMEO Chemicals
  • First Aid: (General first aid procedures); Eye: Irrigate immediately - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.; Skin: Water flush promptly - If this chemical contacts the skin, flush the contaminated skin with water promptly. If this chemical penetrates the clothing, immediately remove the clothing and flush the skin with water promptly. If irritation persists after washing, get medical attention.; Breathing: Respiratory support; Swallow: Medical attention immediately - If this chemical has been swallowed, get medical attention immediately. Source: The National Institute for Occupational Safety and Health (NIOSH)
  • Signal: Danger Source: European Chemicals Agency (ECHA)
  • GHS Hazard Statements: H226 (99.2%): Flammable liquid and vapor [Warning Flammable liquids]; H302 (17.7%): Harmful if swallowed [Warning Acute toxicity, oral]; H315 (69.5%): Causes skin irritation [Warning Skin corrosion/irritation]; H318 (10.3%): Causes serious eye damage [Danger Serious eye damage/eye irritation]; H319 (70.4%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]; H332 (80.5%): Harmful if inhaled [Warning Acute toxicity, inhalation]; H335 (82.6%): May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation] Source: European Chemicals Agency (ECHA)
  • Precautionary Statement Codes: P210, P233, P240, P241, P242, P243, P261, P264, P264+P265, P270, P271, P280, P301+P317, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P305+P354+P338, P317, P319, P321, P330, P332+P317, P337+P317, P362+P364, P370+P378, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement) Source: European Chemicals Agency (ECHA)
  • ECHA C&L Notifications Summary: Aggregated GHS information provided per 2589 reports by companies from 47 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.; Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website. Source: European Chemicals Agency (ECHA)
  • Signal: Warning Source: European Chemicals Agency (ECHA)
  • GHS Hazard Statements: H226 (52.2%): Flammable liquid and vapor [Warning Flammable liquids]; H315 (47.8%): Causes skin irritation [Warning Skin corrosion/irritation]; H319 (47.8%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]; H332 (100%): Harmful if inhaled [Warning Acute toxicity, inhalation]; H335 (100%): May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation] Source: European Chemicals Agency (ECHA)
  • Precautionary Statement Codes: P210, P233, P240, P241, P242, P243, P261, P264, P264+P265, P271, P280, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P317, P319, P321, P332+P317, P337+P317, P362+P364, P370+P378, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement) Source: European Chemicals Agency (ECHA)
  • ECHA C&L Notifications Summary: Aggregated GHS information provided per 115 reports by companies from 4 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.; Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website. Source: European Chemicals Agency (ECHA)
  • Signal: Danger Source: NITE-CMC
  • GHS Hazard Statements: H226: Flammable liquid and vapor [Warning Flammable liquids]; H302: Harmful if swallowed [Warning Acute toxicity, oral]; H318: Causes serious eye damage [Danger Serious eye damage/eye irritation]; H335: May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]; H336: May cause drowsiness or dizziness [Warning Specific target organ toxicity, single exposure; Narcotic effects] Source: NITE-CMC
  • Precautionary Statement Codes: P210, P233, P240, P241, P242, P243, P261, P264, P264+P265, P270, P271, P280, P301+P317, P303+P361+P353, P304+P340, P305+P354+P338, P317, P319, P330, P370+P378, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement) Source: NITE-CMC
  • GHS Hazard Statements: H226: Flammable liquid and vapor [Warning Flammable liquids]; H303: May be harmful if swallowed [Warning Acute toxicity, oral]; H313: May be harmful in contact with skin [Warning Acute toxicity, dermal]; H319: Causes serious eye irritation [Warning Serious eye damage/eye irritation]; H335: May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]; H336: May cause drowsiness or dizziness [Warning Specific target organ toxicity, single exposure; Narcotic effects]; H370: Causes damage to organs [Danger Specific target organ toxicity, single exposure] Source: NITE-CMC
  • NFPA Health Rating: 1 - Materials that, under emergency conditions, can cause significant irritation. Source: Hazardous Substances Data Bank (HSDB)
  • NFPA Fire Rating: 2 - Materials that must be moderately heated or exposed to relatively high ambient temperatures before ignition can occur. Materials would not under normal conditions form hazardous atmospheres with air, but under high ambient temperatures or under moderate heating could release vapor in sufficient quantities to produce hazardous atmospheres with air. Source: Hazardous Substances Data Bank (HSDB)
  • NFPA Instability Rating: 0 - Materials that in themselves are normally stable, even under fire conditions. Source: Hazardous Substances Data Bank (HSDB)
  • Environmental Bioconcentration: The BCF for isopentanol estimated from isopentanol's octanol/water partition coefficient, log 1.42(1), using a recommended regression equation is 7(2). Such a low BCF would indicate that isopentanol would not bioconcentrate in aquatic organisms(SRC). Source: Hazardous Substances Data Bank (HSDB)
  • Environmental Fate: TERRESTRIAL FATE: In view of isopentanol's relatively high vapor pressure, 2.37 mm Hg at 25 °C(1), moderate Henry's Law constant, 1.41X10-5 atm-cu m/mol(2), and low adsorptivity to soil, isopentanol would be expected to volatilize from dry and moist soil(SRC). It is highly mobile in soil and should leach. Isopentanol is readily biodegraded in screening tests as well as in water grab sample tests and therefore would be expected to biodegrade in soil. (SRC) Source: Hazardous Substances Data Bank (HSDB)
  • Environmental Fate: AQUATIC FATE: If released in water, isopentanol will be lost by volatilization. The volatilization half-life of isopentanol from a model river estimated from its Henry's Law constant, 1.41X10-5 atm-cu m/mol(1), is 2.55 days(2). It should also biodegrade. The half-life of isopentanol in groundwater, river water and Lake Superior harbor water in Minnesota were 15, 11, and 6.1 days, respectively(3). Isopentanol would not be expected to adsorb to sediment or bioconcentrate in aquatic organisms. Source: Hazardous Substances Data Bank (HSDB)
  • Environmental Fate: ATMOSPHERIC FATE: Isopentanol will react with photochemically-produced hydroxyl radicals in the atmosphere. The rate constant estimated for this reaction is 7.8X10-12 cu cm/molec-sec(1). Assuming a hydroxyl radical concn of 5X10+5 radicals/cu cm, the half-life of isopentanol in the atmosphere will be 2.0 days(SRC). Source: Hazardous Substances Data Bank (HSDB)

Mapped by: Existing checksum-valid CAS to unique PubChem CID match. Retrieved: 2026-08-31. Open source record

Scientific classifications and hazard annotations provide context and do not replace the market-specific regulatory decision shown above.

Additional source coverage and match status
SourceResultChecked
NIH PubChem PUG-ViewExact match2026-08-31

A recorded no-match is useful evidence that the source was checked; it is not a claim that the substance does not exist elsewhere.

Retrieved from NIH PubChem on 2026-08-31 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.

Records for CAS 123-51-3

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How CAS 123-51-3 is used on this site

CAS 123-51-3 is the Chemical Abstracts Service identifier used to pin this page to a specific substance. In the current dataset, 0 EU annex records share this identifier, which helps you cross-check whether the same substance appears under one regulatory context or several.

Use this page when a supplier specification, SDS or raw-material dossier gives you CAS 123-51-3 and you need to see every linked Annex II–VI record in one place. The entry cards above are the quickest route to concentration limits, warnings, annex placement and product-type conditions.