2-Methyl-2-butanol

HCID 6405CAS 75-85-4

Grundinformationen

Standard-SMILES
CCC(C)(C)O
InChIKey
MSXVEPNJUHWQHW-UHFFFAOYSA-N
Summenformel
C5H12O
Durchschnittliche Molmasse
88,15 g/mol
Monoisotopische Masse
88,088815

Überblick

Tert-amyl alcohol appears as a clear, colorless liquid with an odor of camphor. Slightly soluble in water.

Namen und Bezeichner

Bevorzugter Name
2-Methyl-2-butanol
IUPAC
2-methylbutan-2-ol
Lokaler Name
2-Methylbutanol-2
Englischer Name
2-Methyl-2-butanol
Summenformel
C5H12O
Molmasse
88.15

Namen und Synonyme

2-METHYL-2-BUTANOLtert-Amyl alcohol75-85-42-Methylbutan-2-olAmylene hydratetert-Pentyl alcoholtert-Pentanolt-Amyl alcohol2-Butanol, 2-methyl-Ethyldimethylcarbinolt-Pentyl alcohol1,1-Dimethyl-1-propanol
Weitere Namen anzeigen
tAmOHt-amyl2-methyl-2-butano
Dimethylethylcarbinoltert-Isoamyl alcohol3-Methylbutan-3-olDimethyl ethyl carbinolEthyl dimethyl carbinol2-Methyl butanol-2Amylenum hydratumAmylalkohol, tertiaerer

Datenbank-Bezeichner

CAS
75-85-4
PubChem CID
6405
DTXSID
DTXSID0041436
ChEMBL
CHEMBL44658
ChEBI
CHEBI:132750
UNII
69C393R11Z
EC Number
200-908-9
Nikkaji
J4.164E

Eigenschaften

Berechnete Struktureigenschaften

XLogP
0,9
Polarare Oberfläche (TPSA)
20,2 Ų
H-Brücken-Donoren
1
H-Brücken-Akzeptoren
1
Frei drehbare Bindungen
1
Schwere Atome
6

Experimentelle und physikochemische Eigenschaften

Chemical Classes · 2 Einträge

Flammable agents - 3rd degree

Volatile Organic Compound (VOC)

SolventsSolvents -> Alcohols (<C12)
pHSolution neutral to litmus
SpringerMaterials PropertiesBoiling point
FragrancesFragrance Ingredient (2-Methyl-2-butanol) -> IFRA transparency List
LogP · 2 Einträge

log Kow = 0.89

0.89

Physikochemische Eigenschaften

Schmelzpunkt
-12 °C · -12 °C
Siedepunkt
102 °C · 102 °C(lit.)
Dichte
0.805 g/mL · 0.805 g/mL at 25 °C(lit.)
Dampfdichte
3 · 3 (vs air)
Dampfdruck
15.5 hPa · 15.5 hPa (20 °C)
Brechungsindex
20 · n20/D 1.405(lit.)

Sicherheit und Regulatorisches

GHS-Klassifizierung

GHS Classification · 6 Einträge

Danger

H225: Highly Flammable liquid and vapor [Danger Flammable liquids]

P210, P233, P240, P241, P242, P243, P261, P264, P271, P280, P302+P352, P303+P361+P353, P304+P340, P317, P319, P321, P332+P317, P362+P364, P370+P378, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement)

This chemical does not meet GHS hazard criteria for 1.8% (11 of 610) of reports.

Danger

H225 (98.2%): Highly Flammable liquid and vapor [Danger Flammable liquids]

Gefahrenhinweise

Regulatory Information · 6 Einträge

Chemical: 2-Butanol, 2-methyl-

Commission Regulation (EC) No 1565/2000 (Repealed by Com. Implementing Reg. (EU) No 872/2012)

2-Butanol, 2-methyl- is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of 2-Butanol, 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: 13-08-2020 https://echa.europa.eu/registration-dossier/-/registered-dossier/10040

2-Methylbutan-2-ol: Does not have an individual approval but may be used under an appropriate group standard

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.)

DOT LabelFlammable Liquid
Fire HazardsExcerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]:
Fire PotentialFLAMMABLE, DANGEROUS FIRE RISK.
Health HazardsExcerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]:
Hazards SummaryDangerous fire risk; [Hawley] A skin, eye, and respiratory tract irritant; Inhalation of high concentrations may cause CNS effects; [HSDB] An irritant; Inhalation of high concentrations can cause CNS depression; [MSDSonline]

Sicherheit und Schutzausrüstung

Fire FightingExcerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]:
First AidExcerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]:
Exposure Control and Personal Protection20.0 [ppm]
Fire Fighting Procedures · 1 Eintrag

If material on fire or involved in fire: Do not extinguish fire unless flow can be stopped or safely confined. Use water in flooding quantities as fog. Solid streams of water may be ineffective. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use "alcohol" foam, dry chemical or carbon dioxide. /Amyl alcohols/

Storage Conditions · 2 Einträge

Prior to working with this chemical you should be trained on its proper handling and storage. Before entering a confined space where amyl alcohols may be present, check to make sure that an explosive concentration does not exist. Store in tightly closed containers in a cool, well ventilated area away from strong oxidizers, strong acids, and hydrogen trifluoride since violent reactions occur. Metal containers involving the transfer of this chemical should be grounded and bonded. Where possible, automatically pump liquid from drums or other storage containers to process containers. Drums must be equipped with self-closing valves, pressure vacuum bungs, and flame arresters. Use only non-sparking tools and equipment, especially when opening and closing containers of this chemical. Sources of ignition such as smoking and open flames are prohibited where this chemical is used, handled, or stored in a manner that could create a potential fire or explosion hazard. /Amyl alcohols/

KEEP TIGHTLY CLOSED & PROTECTED FROM LIGHT.

Cleanup Methods · 5 Einträge

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 similar material and deposit in sealed containers. It may be necessary to contain and dispose of this chemical as a hazardous waste. If material or contaminated runoff enters waterways, notify downstream users of potentially contaminated waters. Contact your Department of Environmental Protection or your regional office of the federal EPA for specific recommendations. If employees are required to clean up spills, they must be properly trained and equipped. OSHA 1910.120(q) may be applicable. /Amyl alcohols/

The objective of this study was to operate a novel, field-scale, aerobic bioreactor and assess its performance in the ex situ treatment of groundwater contaminated with gasoline from a leaking underground storage tank in Pascoag, RI. The groundwater contained elevated concentrations of MTBE (methyl tert-butyl ether), TBA (tert-butyl alcohol), TBF (tert-butyl formate), BTEX (benzene, toluene, ethyl benzene, and xylene isomers), and other gasoline additives (tert-amyl methyl ether, di-isopropyl ether, tert-amyl alcohol, methanol, and acetone). The bioreactor was a gravity-flow membrane-based system called a Biomass Concentrator Reactor (BCR) designed to retain all biomass within the reactor. It was operated for six months at an influent flow rate that ultimately reached 5 gpm. The goal was to achieve a removal of all contaminants to <5 ug/L, which is the California Drinking Water advisory for MTBE. The concentration of TBA, an MTBE biodegradation byproduct, was consistently lower than that of MTBE. The other daughter compound detected in the influent, TBF, was degraded to concentrations below the detection limit of 0.02 ug/L. BTEX were consistently degraded to significantly lower levels in the effluent throughout the duration of the study (<1 ug/L). A similar high removal efficiency of the other gasoline oxygenates present in the groundwater (TAME, DIPE, and TAA) was also achieved. ...

Environmental considerations-land spill: Dig a pit, pond, lagoon, holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with an impermeable flexible membrane liner./ Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Absorb bulk liquid with fly ash, cement powder, or commercial sorbents. /Amyl alcohols/

Environmental considerations-water spill: Use natural barriers or oil spill control booms to limit spill travel. Remove trapped material with suction hoses. /Amyl alcohols/

Environmental considerations-air spill Apply water spray or mist to knock down vapors. /Amyl alcohols, combustible liquid/

Toxikologische Informationen

Body Burden · 1 Eintrag

The urine of Finnish gasoline road-tanker drivers involved in loading and unloading 95- and 98-octane unleaded gasoline contained 2-methyl-2-butanol, a metabolite of methyl tert-amyl ether, at concentrations of 40 nmol/L (first urine after the work shift) and 20 nmol/L (next morning sample)(1). 2-Methyl-2-butanol was not detected in either blood or urine samples of gasoline road-tanker drivers collected in either October 1994 (n=13, urine; n=14, blood) or August 1995 (n=20, blood and urine samples; limit of quantitation <100 nmol/L)(2).

Interactions · 1 Eintrag

2-Methyl-2-butanol (4.1 mmol/kg) induced a behavioral intoxication in rats (male, Sprague-Dawley, 160 to 300 g) at 8 min after the intraperitoneal administration of the pentanol. The intoxication was scored on a scale of 0 to 4, where 3 = 'very little or no recovery of righting reflex, heavy sedation, no spontaneous locomotor activity, flaccid muscles, absence of pelvic and abdominal elevation' and 2 = 'heavy sedation, pronounced motor coordination and sluggish movement, limbs extended away from the body'. After 2-methyl-2-butanol alone the intoxication was scored as approximately 2.9. The prior administration of the imidazobenzodiazepine Ro15-4513 (5 min before the alcohol) partially reversed the intoxication by 2-methyl-2-butanol and the score decreased to approximately 1.8. The Ro15-4513 was more effective at reducing the intoxication after treatment with ethanol than after treatment with the pentanol.

Ecotoxicity Values · 2 Einträge

EC50; Species: Daphnia magna (Water flea); Conditions: freshwater, static, pH 8; Concentration: 3185 mg/L for 24 hr; Effect: behavior, equilibrium

LC50; Species: Daphnia magna (Water flea, age < or =24 hr); Conditions: freshwater, static, 20-22 °C, pH 7.6-7.7, hardness 16 degrees hardness (dH); Concentration: 4030 mg/L for 24 hr

Environmental Fate · 3 Einträge

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 73(SRC), determined from a log Kow of 0.89(2) and a regression-derived equation(3), indicates that 2-methyl-2-butanol is expected to have high mobility in soil(SRC). Volatilization of 2-methyl-2-butanol from moist soil surfaces is expected to be an important fate process(SRC) given a Henry's Law constant of 1.38X10-5 atm-cu m/mole(4). 2-Methyl-2-butanol is expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 16.7 mm Hg(5). 2-Methyl-2-butanol is expected to be resistant to biodegradation in soil(SRC) based on results from several screening studies (6-9). 2-Methyl-2-butanol contains a tertiary structure which is expected to decrease its biodegradability(10).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 73(SRC), determined from a log Kow of 0.89(2) and a regression-derived equation(3), indicates that 2-methyl-2-butanol is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon a Henry's Law constant of 1.38X10-5 atm-cu m/mole(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 2 and 22 days, respectively(SRC). According to a classification scheme(5), an estimated BCF of 3(SRC), from its log Kow(2) and a regression-derived equation(6), suggests the potential for bioconcentration in aquatic organisms is low(SRC). 2-Methyl-2-butanol is expected to be resistant to biodegradation in water(SRC) based on results from several screening studies (7-10). 2-Methyl-2-butanol contains a tertiary structure which is expected to decrease its biodegradability(11).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 2-methyl-2-butanol, which has a vapor pressure of 16.7 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 2-methyl-2-butanol 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 3.3 days(SRC), calculated from its rate constant of 4.9X10-12 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). 2-Methyl-2-butanol does not contain chromophores that absorb at wavelengths >290 nm(4) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

Food Survey Values2-Methyl-2-butanol has been identified as a volatile in cassava(1) and fried bacon(2).
Adverse EffectsNeurotoxin - Acute solvent syndrome

Sicherheitsdaten

OEB
A
OEL
TWA: 100.0 ppm; 360.0 mg/m3, STEL: 125.0 ppm; 450.0 mg/m3
wgk
1
tsca
TSCA listed
ridadr
UN 1105 3/PG 2
hs_code
29051500

Chemie und Industrie

Pharmakologische Informationen

Biological Half-Life · 2 Einträge

Upon repeated exposure to 50 ppm, the material /2-methyl-2-butanol/ was cleared by rats (t1/2 = 47 min) and dogs (t1/2 = 69 min) in an apparent first-order manner.

Following repeated exposure to 1000 ppm the plasma clearance was more rapid in the mouse than in either the rat or the dog exposed to 50 ppm, the t1/2 times being 29, 47, and 69 min, respectively ... The data demonstrate that the kinetics of tert-amyl alcohol are highly species- and conc-dependent.

Metabolism/Metabolites · 6 Einträge

... the biotransformation of tert-Amyl methyl ether (TAME) /was studied/ in rats and one human volunteer after inhalation of (12)C- or (13)C-labeled TAME. In addition, the biotransformation of [(13)C]-tert-amyl alcohol was studied in rats after gavage. ... Rats (two males and two females) were individually exposed to 2000 ppm [(12)C]- or [(13)C]TAME for 6 hr, and urine was collected for 48 hr. Free and glucuronidated 2-methyl-2,3-butanediol and a glucuronide of tert-amyl alcohol were identified ... as major urinary metabolites on the basis of the relative intensities of the (13)C NMR signals. The presence of several minor metabolites was also indicated by (13)C NMR; they were identified as tert-amyl alcohol, 2-hydroxy-2-methylbutyric acid, and 3-hydroxy-3-methylbutyric acid. One human volunteer was exposed to an initial concentration of 27,000 ppm [(13)C]TAME by inhalation for 4 min from a 2 L gas sampling bag, and metabolites of TAME excreted in urine were analyzed by (13)C NMR. All TAME metabolites identified in rats were also present in the human urine samples. To study tert-amyl alcohol biotransformation, male rats (n = 3) were treated with 250 mg/kg [(13)C]-tert-amyl alcohol dissolved in corn oil by gavage, and urine was collected for 48 hr. (13)C NMR of the urine samples showed the presence of metabolites identical to those in the urine of [(13)C]TAME-treated rats. Our results suggest that TAME is extensively metabolized by rats and humans to tert-amyl alcohol which may be further oxidized to diols and carboxylic acids. These reactions are likely mediated by cytochrome P450-dependent oxidations.

... The objective of this study was to use a physiologically-based pharmacokinetic (PBPK) model to describe the disposition of tert-amyl methyl ether (TAME) and its major metabolite, tert-amyl alcohol (TAA), in male Fischer-344 rats. The model compartments for TAME and TAA were flow-limited. The TAME physiological model had 6 compartments: lung, liver, rapidly perfused tissues, slowly perfused tissues, fat, and kidney. The TAA model had 3 compartments: lung, liver, and total-body water. The 2 models were linked through metabolism of TAME to TAA in the liver. Model simulations were compared with data on blood concentrations of TAME and TAA taken from male Fischer-344 rats during and after a 6-hour inhalation exposure to 2500, 500, or 100 ppm TAME. The PBPK model predicted TAME pharmacokinetics when 2 saturable pathways for TAME oxidation were included. The TAA model, which included pathways for oxidation and glucuronide conjugation of TAA, underpredicted the experimental data collected at later times postexposure. To account for biological processes occurring during this time, three hypotheses were developed: nonspecific binding of TAA, diffusion-limited transport of TAA, and enterohepatic circulation of TAA glucuronide. These hypotheses were tested using three different model structures. Visual inspection and statistical evaluation involving maximum likelihood techniques indicated that the model incorporating nonspecific binding of TAA provided the best fit to the data. ...

The biotransformation of ... tert-amyl methyl ether (TAME) was studied in humans and in rats after inhalation of 4 and 40 ppm of ... TAME ... for 4 hours, and the biotransformation of ... TAME was studied after ingestion exposure in humans to 5 and 15 mg in water. .../Following ingestion/ tert-Amyl alcohol (TAA), free and glucuronidated 2-methyl-2,3-butanediol (a glucuronide of TAA), 2-hydroxy-2-methyl butyrate, and 3-hydroxy-3-methyl butyrate were found to be metabolites of TAME. After inhalation ... TAME /was/ rapidly taken up by both rats and humans; after termination of exposure, clearance from blood of the ethers by exhalation and biotransformation to urinary metabolites occurred with half-times of less than 7 hours in rats and humans. ... Biotransformation of TAME was qualitatively similar in rats and humans, but the metabolic pathways were different. In humans, 2-methyl-2,3-butanediol, 2-hydroxy-2-methyl butyrate, and 3-hydroxy-3methyl butyrate were recovered as major urinary products. In rats, however, 2-methyl-2,3-butanediol and its glucuronide were major TAME metabolites recovered in urine. After ingestion ... TAME /was/ ... rapidly absorbed from the gastrointestinal tract. Hepatic first-pass metabolism ... was not observed, and a significant part of the administered dose was transferred into blood and cleared by exhalation. Metabolic pathways for ... TAME and kinetics of excretion were identical after ingestion and inhalation exposures. ...

... Male mice of ICR strain were exposed to about 5% /isopentane/ for one hour while the oxygen in the environmental air was maintained at about 20%. Then their blood and liver tissue were collected and analyzed by means of GC and GC-MS. The metabolites thus obtained were ... 3-methyl-2-butanol, 2-methyl-2-butanol and 3-methyl-2-butanone were detected as the resultant metabolites. In the presence of the NADPH-generating system liver microsomes were made to react to the substrate of saturated ... isopentane aqueous solution at 37 degrees C for one hour. As a result, the same metabolites were produced as obtained in the exposure experiment. It was therefore suggested that ... isopentane /was/ metabolized chiefly by liver microsomes. Male mice of ICR strain were fed with 80 mg/kg b.w. of phenobarbital for consecutive four days and exposed to ... isopentane for one hour. This resulted in an increase in the amount of ... 2-methyl-2-butanol in the isopentane inhalation experiment. ...

For more Metabolism/Metabolites (Complete) data for 2-METHYL-2-BUTANOL (7 total), please visit the HSDB record page.

Tert-amyl alcohol is a known human metabolite of tert-amyl methyl ether.

Absorption, Distribution and Excretion · 5 Einträge

Dog weighing 11 kg, when injected sc with dose of 0.1 mL of 2-methyl-2-butanol...exhaled 65% of it within 5.75 hr. Another dog given slightly larger dose of same alc iv exhaled 52% within 6 hr. Cats also exhaled large quantity unchanged.

When rabbits were injected with 2 levels of dosage ... they exhaled, in first instance 21% of alc in unchanged form within 4 hr, & in second, 22% within 3 hr. ... rat given 1 g/kg of same isomer eliminated 26.4% unchanged in expired air and 8.9% in the urine within 50 hr.

The rate of elimination of amyl alcohols from the blood of rats decreases in the order of primary, secondary, and tertiary. tert-Amyl alcohol did not disappear from the blood of rats until 50 hr following an ip dose of 1 g/kg.

Small amts of the primary and secondary alcohols, and appreciable amts of the tertiary isomer, are excreted unchanged in the respired air and urine. /Amyl alcohols/

... /The authors/ Found a conc of 12.5 mg percent of tert-amyl alcohol in the blood of rats 1 hr following an ip dose of 1.0 kg. They also found a conc of 191 mg percent in the jugular blood of rats at the time of death from respiratory failure. Conc in the plasma of rats about 0.6 hr after they had inhaled 150, 500, or 1500 ppm of tert-amyl alcohol for 6 hr were 9.6, 59.9, and 337 ug/mL, respectively.

Cellular LocationsCytoplasm

Verwendung und Herstellung

Uses · 6 Einträge

Used as a solvent in flavors, pharmaceuticals, corrosion inhibitors, resins, gums, coating materials, and other chemicals; Also used in organic synthesis and as a frothing agent (ore flotation), surfactant (petroleum recovery), and stabilizing agent; [HSDB]

Painting (Solvents) [Category: Paint]

Used as a solvent in synthetic flavoring, pharmaceuticals, corrosion inhibitors, and making plastics and other chemicals. /Amyl alcohols/

Solvent, flotation agent; organic synthesis ...

SOLVENT FOR RESINS AND GUMS PHARMACEUTICAL SOLVENT FOR TRIBROMOETHANOL SOLN; FROTHING AGENT FOR ORE FLOTATION PROCESSES; MEDICATION: SEDATIVE-HYPNOTIC DRUG; CHEM INT FOR SYNTHESIS OF ITS DERIVATIVES

In formulations for stabilizing 1,1,1-trichloroethane used for degreasing metals, rosin flux removal and dry cleaning. Used as a solvent in the preparation of epoxy-containing novolak resins with low chloride content and in mixtures with surfactants in petroleum recovery by flooding.

ImpuritiesTypical impurities are other monomeric alcohols, dimeric alcohols, acetals and several miscellaneous substances ... typically free of suspended matter.
U.S. Production · 3 Einträge

2023: 50,000 - <250,000 lb

Production volumes for non-confidential chemicals reported under the Inventory Update Rule. [Table#4994]

This chemical is listed as an Extended High Production Volume (EHPV). Chemicals listed as EHPV were produced in or imported into the U.S. in >1 million pounds according to the 2002 Toxic Substances Control Act (TSCA) Inventory Update. The EHPV program is a voluntary initiative that allows companies to demonstrate that adequate screening data exist for organic HPV chemicals.

Industry UsesIntermediate
Methods of Manufacturing · 4 Einträge

Prepared from 2-methyl-2-butene alone and mixed with 2-methyl-1-butene.

... by fractionation of fusel oil ...

Oxo process: 1-butene, 2-butene and isobutylene react with a mixture of carbon monoxide and hydrogen in presence of a metal catalyst to form isomer mixture of C5 aldehyde which is then hydrogenated to corresponding amyl alcohol. /Amyl alcohols/

... Produced mainly by hydration of pentenes.

Formulations/PreparationsGrades: Technical; CP; NF.
Anwendungen · 1 Eintrag

Verwenden2-Methyl-2-butanol is used as a solvent in flavors, pharmaceuticals, corrosion inhibitors, resins, gums, coating materials and in organic synthesis. It acts as a frothing agent (ore flotation), surfactant (petroleum recovery) and stabilizing agent. Further, it is used in processing aids.

Anbieter50 Anbieter

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Shandong chuangyingchemical Co., Ltd.18853181302 · [email protected]

Ergänzende Hinweise

DefinitionChEBI: A tertiary alcohol that is propan-1-ol in which both of the hydrogens at position 1 have been replaced by methyl groups.

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2-Methyl-2-butanol (HCID 6405)|Huagongshe