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2,2-Dimethylbutane

PubChem CID
6403
Structure
2,2-Dimethylbutane_small.png
2,2-Dimethylbutane_3D_Structure.png
2,2-Dimethylbutane__Crystal_Structure.png
Molecular Formula
Synonyms
  • 2,2-DIMETHYLBUTANE
  • Neohexane
  • 75-83-2
  • Butane, 2,2-dimethyl-
  • HSDB 75
Molecular Weight
86.18 g/mol
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Dates
  • Create:
    2005-03-26
  • Modify:
    2025-01-18
Description
Neohexane is a colorless liquid with an odor of gasoline. Less dense than water and insoluble in water. Hence floats on water. Irritating vapor. Flash point -54 °F.
2,2-Dimethylbutane is an isomer of hexane. Hexane is a chemical made from crude oil. It is highly flammable, and its vapors can be explosive. Pure hexane is used in laboratories. Most of the hexane used in industry is mixed with similar chemicals called solvents. The major use for solvents containing hexane is to extract vegetable oils from crops such as soybeans. These solvents are also used as cleaning agents in the printing, textile, furniture, and shoemaking industries. Certain kinds of special glues used in the roofing and shoe and leather industries also contain hexane. Several consumer products contain hexane, such as gasoline, quick-drying glues used in various hobbies, and rubber cement. (L175)
L175: Wikipedia. Methanol. Last Updated 19 May 2009. http://en.wikipedia.org/wiki/Methanol

1 Structures

1.1 2D Structure

Chemical Structure Depiction
2,2-Dimethylbutane.png

1.2 3D Conformer

1.3 Crystal Structures

1 of 2
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COD Number
Associated Article
Bąk, Joanna M.; Gajda, Roman; Woźniak, Krzysztof. New High Pressure Crystal Structures of 2,2-Dimethylbutane and 2,3-Dimethylaniline: Combined X-ray, Raman, and Theoretical Studies. Crystal Growth & Design 2015;15(1):45-. DOI: 10.1021/cg500998g
Crystal Structure Depiction
Crystal Structure Depiction
Hermann-Mauguin space group symbol
P n m a
Hall space group symbol
-P 2ac 2n
Space group number
62
a
9.8263 Å
b
8.162 Å
c
6.9926 Å
α
90.00 °
β
90.00 °
γ
90.00 °
Z
4
Z'
0.5
Residual factor
0.0768

2 Names and Identifiers

2.1 Computed Descriptors

2.1.1 IUPAC Name

2,2-dimethylbutane
Computed by Lexichem TK 2.7.0 (PubChem release 2021.10.14)

2.1.2 InChI

InChI=1S/C6H14/c1-5-6(2,3)4/h5H2,1-4H3
Computed by InChI 1.0.6 (PubChem release 2021.10.14)

2.1.3 InChIKey

HNRMPXKDFBEGFZ-UHFFFAOYSA-N
Computed by InChI 1.0.6 (PubChem release 2021.10.14)

2.1.4 SMILES

CCC(C)(C)C
Computed by OEChem 2.3.0 (PubChem release 2024.12.12)

2.2 Molecular Formula

C6H14
Computed by PubChem 2.2 (PubChem release 2021.10.14)

2.3 Other Identifiers

2.3.1 CAS

75-83-2

2.3.2 European Community (EC) Number

2.3.3 UNII

2.3.4 UN Number

2.3.5 ChEMBL ID

2.3.6 DSSTox Substance ID

2.3.7 HMDB ID

2.3.8 Metabolomics Workbench ID

2.3.9 Nikkaji Number

2.3.10 NSC Number

2.3.11 Wikidata

2.3.12 Wikipedia

2.4 Synonyms

2.4.1 Depositor-Supplied Synonyms

3 Chemical and Physical Properties

3.1 Computed Properties

Property Name
Molecular Weight
Property Value
86.18 g/mol
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
XLogP3-AA
Property Value
3
Reference
Computed by XLogP3 3.0 (PubChem release 2021.10.14)
Property Name
Hydrogen Bond Donor Count
Property Value
0
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Hydrogen Bond Acceptor Count
Property Value
0
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Rotatable Bond Count
Property Value
1
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Exact Mass
Property Value
86.109550447 Da
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
Monoisotopic Mass
Property Value
86.109550447 Da
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
Topological Polar Surface Area
Property Value
0 Ų
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Heavy Atom Count
Property Value
6
Reference
Computed by PubChem
Property Name
Formal Charge
Property Value
0
Reference
Computed by PubChem
Property Name
Complexity
Property Value
29.8
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Isotope Atom Count
Property Value
0
Reference
Computed by PubChem
Property Name
Defined Atom Stereocenter Count
Property Value
0
Reference
Computed by PubChem
Property Name
Undefined Atom Stereocenter Count
Property Value
0
Reference
Computed by PubChem
Property Name
Defined Bond Stereocenter Count
Property Value
0
Reference
Computed by PubChem
Property Name
Undefined Bond Stereocenter Count
Property Value
0
Reference
Computed by PubChem
Property Name
Covalently-Bonded Unit Count
Property Value
1
Reference
Computed by PubChem
Property Name
Compound Is Canonicalized
Property Value
Yes
Reference
Computed by PubChem (release 2021.10.14)

3.2 Experimental Properties

3.2.1 Physical Description

Neohexane is a colorless liquid with an odor of gasoline. Less dense than water and insoluble in water. Hence floats on water. Irritating vapor. Flash point -54 °F.
Colorless liquid with mild gasoline-like odor; [ACGIH]
Clear liquids with mild, gasoline-like odors.

3.2.2 Color / Form

Colorless liquid
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 880

3.2.3 Boiling Point

121.5 °F at 760 mmHg (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
49.7 °C
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 94th Edition. CRC Press LLC, Boca Raton: FL 2013-2014, p. 3-206
121.5 °F

3.2.4 Melting Point

-148 °F (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
-99.9 °C
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 94th Edition. CRC Press LLC, Boca Raton: FL 2013-2014, p. 3-206
-148 °F

3.2.5 Flash Point

-54 °F (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
-54 °F (-48 °C) closed cup
National Fire Protection Association; Fire Protection Guide to Hazardous Materials. 14TH Edition, Quincy, MA 2010, p. 325-49
-54 °F

3.2.6 Solubility

less than 1 mg/mL at 72 °F (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
In water, 21.2 mg/L at 25 °C
Yalkowsky, S.H., He, Yan, Jain, P. Handbook of Aqueous Solubility Data Second Edition. CRC Press, Boca Raton, FL 2010, p. 319
Soluble in ethanol, diethyl ether; very soluble in acetone, benzene, petroleum ether, carbon tetrachloride
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 94th Edition. CRC Press LLC, Boca Raton: FL 2013-2014, p. 3-206

3.2.7 Density

0.649 at 68 °F (USCG, 1999) - Less dense than water; will float
U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
0.6444 g/cu cm at 25 °C
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 94th Edition. CRC Press LLC, Boca Raton: FL 2013-2014, p. 3-206
0.649

3.2.8 Vapor Density

3 (NTP, 1992) - Heavier than air; will sink (Relative to Air)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
3.0 (Air = 1)
Fire Protection Guide to Hazardous Materials. 12 ed. Quincy, MA: National Fire Protection Association, 1997., p. 325-42
3

3.2.9 Vapor Pressure

274 mmHg at 70 °F ; 400 mmHg at 87.8 °F (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
319.0 [mmHg]
319 mm Hg at 25 °C
Boublik, T., Fried, V., and Hala, E., The Vapour Pressures of Pure Substances. Second Revised Edition. Amsterdam: Elsevier, 1984.
274 mmHg

3.2.10 LogP

log Kow = 3.82
Hansch, C., Leo, A., D. Hoekman. Exploring QSAR - Hydrophobic, Electronic, and Steric Constants. Washington, DC: American Chemical Society., 1995., p. 24

3.2.11 Autoignition Temperature

797 °F (USCG, 1999)
U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
761 °F (405 °C).
National Fire Protection Association; Fire Protection Guide to Hazardous Materials. 14TH Edition, Quincy, MA 2010, p. 325-49

3.2.12 Heat of Combustion

4159.5 kJ/mol
Lide, D.R. (ed.). CRC Handbook of Chemistry and Physics. 73rd ed. Boca Raton, FL: CRC Press Inc., 1992-1993., p. 5-87

3.2.13 Heat of Vaporization

27.68 kg/mol at 25 °C
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 94th Edition. CRC Press LLC, Boca Raton: FL 2013-2014, p. 3-206

3.2.14 Refractive Index

Index of refraction: 1.3688 at 20 °C/D
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 94th Edition. CRC Press LLC, Boca Raton: FL 2013-2014, p. 3-206

3.2.15 Kovats Retention Index

Standard non-polar
526 , 528.5 , 526.78 , 526.81 , 531 , 528 , 528 , 528 , 535.6 , 537.4 , 540.25 , 533 , 534 , 535.3 , 543.8 , 547.9 , 537.9 , 537.9 , 538 , 538 , 538.2 , 537 , 534 , 538 , 538 , 535 , 536 , 538 , 535.5 , 536.7 , 537.1 , 537.7 , 534 , 535 , 535 , 536 , 537 , 538 , 537.9 , 538 , 536 , 536 , 536 , 537 , 540 , 533 , 534.5 , 534.6 , 536 , 536.1 , 537.7 , 538 , 539.4 , 539.6 , 541.3 , 541.4 , 542.2 , 530 , 538.6 , 539 , 542.16 , 543.36 , 544.75 , 545.8 , 547.42 , 537 , 538 , 540 , 530 , 533 , 538 , 526 , 540 , 537 , 535 , 538 , 538 , 529.3 , 534.1 , 540 , 528 , 538.7 , 532 , 536 , 527.3 , 537 , 536 , 525 , 525 , 533 , 528 , 537 , 536 , 536 , 538 , 529 , 542 , 542 , 536
Semi-standard non-polar
526.3 , 540.8 , 538 , 539 , 535 , 540.9 , 541 , 535.5 , 538.9 , 537.1 , 533.9 , 534.6 , 535.4 , 536.2 , 537 , 537.9 , 536.8 , 537 , 538 , 538 , 540 , 541.7 , 536.9 , 538 , 535.1 , 541.2 , 537 , 538 , 534.99 , 530 , 532 , 533 , 534 , 536 , 537 , 529 , 541 , 538 , 538 , 538 , 535 , 539 , 541 , 535 , 537 , 539 , 540 , 535 , 537 , 538 , 534 , 535 , 536 , 537 , 538 , 539 , 539 , 541 , 530 , 537 , 529.4 , 530 , 538 , 541 , 537 , 537 , 528 , 535
Standard polar
500

3.2.16 Other Experimental Properties

Octane rating: 100+
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 880
Heat capacity: 191.9 J/mol K at 25 °C
Lide, D.R. (ed.). CRC Handbook of Chemistry and Physics. 73rd ed. Boca Raton, FL: CRC Press Inc., 1992-1993., p. 6-122
Heat of fusion: 1.61 cal/g
Lide, D.R. (ed.). CRC Handbook of Chemistry and Physics. 73rd ed. Boca Raton, FL: CRC Press Inc., 1992-1993., p. 5-100
Air Pollution Factors: Manmade sources: evaporation from gasoline fuel tank: 0.1 vol % of total evaporated hydrocarbon's; evaporation from carburetor: 0.0-0.1 vol % of total evaporated hydrocarbon's.
Verschueren, K. Handbook of Environmental Data on Organic Chemicals. Volumes 1-2. 4th ed. John Wiley & Sons. New York, NY. 2001, p. 904
Hydroxyl radical reaction rate constant = 2.32X10-12 cu cm/molec-sec at 25 °C
Atkinson R; J Phys Chem Ref Data Monograph No. 1 (1989)

3.3 SpringerMaterials Properties

3.4 Chemical Classes

3.4.1 Solvents

Solvents -> Aliphatics, Saturated (<C12)

4 Spectral Information

4.1 1D NMR Spectra

1 of 2
1D NMR Spectra
1H NMR: 3406 (Sadtler Research Laboratories Spectral Collection)
2 of 2
1D NMR Spectra

4.1.1 1H NMR Spectra

1 of 3
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Spectra ID
Instrument Type
JEOL
Frequency
90 MHz
Solvent
CDCl3
Shifts [ppm]:Intensity
0.83:41.00, 0.81:38.00, 0.88:44.00, 0.91:34.00, 0.89:42.00, 1.27:22.00, 0.82:143.00, 0.85:1000.00, 1.18:35.00, 0.82:43.00, 0.90:45.00, 0.81:27.00
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Instrument Name
BRUKER AC-300
Source of Sample
Fluka AG, Buchs, Switzerland
Copyright
Copyright © 1991-2024 John Wiley & Sons, Inc. All Rights Reserved.
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4.1.2 13C NMR Spectra

1 of 3
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13C NMR Spectra
13C NMR: 206 (Johnson and Jankowski, Carbon-13 NMR Spectra, John Wiley & Sons, New York)
2 of 3
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Source of Sample
MCB Manufacturing Chemists, Norwood, Ohio
Copyright
Copyright © 1980, 1981-2024 John Wiley & Sons, Inc. All Rights Reserved.
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4.2 Mass Spectrometry

4.2.1 GC-MS

1 of 9
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MoNA ID
MS Category
Experimental
MS Type
GC-MS
MS Level
MS1
Instrument
HITACHI RMU-6M
Instrument Type
EI-B
Ionization Mode
positive
Top 5 Peaks

43 99.99

57 98.50

71 82.50

41 65

29 41

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License
CC BY-NC-SA
2 of 9
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MoNA ID
MS Category
Experimental
MS Type
GC-MS
MS Level
MS1
Instrument
HITACHI RMU-6M
Instrument Type
EI-B
Ionization Mode
positive
Top 5 Peaks

57 99.99

71 86

43 80.20

56 33

41 28.20

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License
CC BY-NC-SA

4.2.2 Other MS

1 of 6
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Other MS
MASS: 563 (NIST/EPA/MSDC Mass Spectral Database, 1990 version); 148 (Atlas of Mass Spectral Data, John Wiley & Sons, New York)
2 of 6
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Authors
YAMAMOTO M, DEP. CHEMISTRY, FAC. SCIENCE, NARA WOMEN'S UNIV.
Instrument
HITACHI RMU-6M
Instrument Type
EI-B
MS Level
MS
Ionization Mode
POSITIVE
Ionization
ENERGY 70 eV
Top 5 Peaks

57 999

43 939

71 810

41 479

56 349

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License
CC BY-NC-SA

4.3 IR Spectra

IR Spectra
IR: 5000 (Sadtler Research Laboratories IR Grating Collection)

4.3.1 FTIR Spectra

1 of 2
Technique
Film on CsI, dried for 2 hours at 50 C in vacuo
Source of Sample
Inter-Montana, Hergeswil
Copyright
Copyright © 1989, 1990-2024 Wiley-VCH Verlag GmbH & Co. KGaA. All Rights Reserved.
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2 of 2
Technique
Film on CsI, dried for 2 hrs at 50c, in vacuum
Source of Spectrum
Spectra and properties provided by Professor Doctor Dieter O. Hummel
Source of Sample
Inter-Montana, Hergeswil, Ch
Copyright
Copyright © 1980, 1981-2024 John Wiley & Sons, Inc. All Rights Reserved.
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4.3.2 ATR-IR Spectra

Technique
ATR-Neat
Copyright
Copyright © 1980, 1981-2024 John Wiley & Sons, Inc. All Rights Reserved.
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4.3.3 Vapor Phase IR Spectra

1 of 2
Instrument Name
DIGILAB FTS-14
Technique
Vapor Phase
Copyright
Copyright © 1980, 1981-2024 John Wiley & Sons, Inc. All Rights Reserved.
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2 of 2
Technique
Vapor Phase
Source of Sample
PHILLIPS PETROLEUM COMPANY, BARTLESVILLE, OKLAHOMA
Copyright
Copyright © 1980, 1981-2024 John Wiley & Sons, Inc. All Rights Reserved.
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4.4 Raman Spectra

1 of 2
Raman Spectra
Raman: 790 (Sadtler Research Laboratories spectral collection)
2 of 2
Catalog Number
D151408
Copyright
Copyright © 2017-2024 Sigma-Aldrich Co. LLC. - Database Compilation Copyright © 2017-2024 John Wiley & Sons, Inc. All Rights Reserved.
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4.5 Other Spectra

SADTLER REF NUMBER: 683 (IR, PRISM)
Weast, R.C. (ed.). Handbook of Chemistry and Physics. 60th ed. Boca Raton, Florida: CRC Press Inc., 1979., p. C-219

6 Chemical Vendors

7 Pharmacology and Biochemistry

7.1 Absorption, Distribution and Excretion

Extensive studies ... have demonstrated that 2,2-dimethylbutane, 2- and 3-methylpentane are distributed in human tissues in very much the same manner as n-pentane and n-hexane, with adipose tissue having a high affinity for all of the C6-alkanes.
Snyder, R. (ed.) Ethel Browning's Toxicity and Metabolism of Industrial Solvents. 2nd ed. Volume 1: Hydrocarbons. Amsterdam - New York - Oxford: Elsevier, 1987., p. 294

7.2 Metabolism / Metabolites

Hexane is mainly absorbed via inhalation, as it is readily absorbed by the lungs. It is distributed throughout the body in the blood, and metabolized by mixed function oxidases in the liver to a number of metabolites. The initial reaction is oxidation by cytochrome P-450 isozymes to hexanols, predominantly 2-hexanol. Further reactions convert 2-hexanol to 2-hexanone, 2,5-hexanediol, 5-hydroxy-2-hexanone, 4,5-dihydroxy-2-hexanone and the neurotoxicant 2,5-hexanedione. Hexane metabolites are excreted in the urine, while unchanged hexane is excreted in expired air. (L175)
L175: Wikipedia. Methanol. Last Updated 19 May 2009. http://en.wikipedia.org/wiki/Methanol

8 Use and Manufacturing

8.1 Uses

EPA CPDat Chemical and Product Categories
The Chemical and Products Database, a resource for exposure-relevant data on chemicals in consumer products, Scientific Data, volume 5, Article number: 180125 (2018), DOI:10.1038/sdata.2018.125
Sources/Uses
Used as solvent (vegetable oils, glues, coatings, and paints); Occur in gasoline, rubber solvent, and petroleum ether; [ACGIH] Used as a high-octane fuel and an intermediate for synthesis of organic chemicals; [Hawley]
ACGIH - Documentation of the TLVs and BEIs, 7th Ed. Cincinnati: ACGIH Worldwide, 2020.
Hawley - Lewis RJ. _Hawley's Condensed Chemical Dictionary, _15th Ed. New York: John Wiley & Sons, 2007.
Component of high-octane motor and aviation fuels; intermediate for agricultural chemicals.
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 880
Pure hexane is used in laboratories. Most of the hexane used in industry is mixed with similar chemicals called solvents. The major use for solvents containing hexane is to extract vegetable oils from crops such as soybeans. These solvents are also used as cleaning agents in the printing, textile, furniture, and shoemaking industries. Certain kinds of special glues used in the roofing and shoe and leather industries also contain hexane. Several consumer products contain hexane, such as gasoline, quick-drying glues used in various hobbies, and rubber cement. (L175)
L175: Wikipedia. Methanol. Last Updated 19 May 2009. http://en.wikipedia.org/wiki/Methanol

8.1.1 Use Classification

Hazard Classes and Categories -> Flammable - 3rd degree

8.1.2 Household Products

Household & Commercial/Institutional Products

Information on 15 consumer products that contain 2,2-Dimethylbutane in the following categories is provided:

• Auto Products

• Commercial / Institutional

• Hobby/Craft

• Home Maintenance

• Home Office

• Inside the Home

8.2 Methods of Manufacturing

Hydroisomerization of 2,3-dimethylbutane in the presence of an acid catalyst
SRI
By the thermal or catalytic union (alkylation) of ethylene and isobutane, both recovered from refinery gases.
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 880

8.3 Formulations / Preparations

Grades: 95%, 99%, research.
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 880

8.4 U.S. Production

(1972) Probably greater than 4.54X10+5 grams
SRI
Production volumes for non-confidential chemicals reported under the Inventory Update Rule.
Year
1986
Production Range (pounds)
No Reports
Year
1990
Production Range (pounds)
No Reports
Year
1994
Production Range (pounds)
>500 thousand - 1 million
Year
1998
Production Range (pounds)
No Reports
Year
2002
Production Range (pounds)
10 thousand - 500 thousand
US EPA; Non-confidential Production Volume Information Submitted by Companies for Chemicals Under the 1986-2002 Inventory Update Rule (IUR). Butane, 2,2-dimethyl- (75-83-2). Available from, as of November 4, 2013: https://epa.gov/cdr/tools/data/2002-vol.html
Production volume for non-confidential chemicals reported under the 2006 Inventory Update Rule. Chemical: 2,2-Dimethylbutane. Aggregated National Production Volume: < 500,000 pounds.
USEPA; Non-Confidential 2006 Inventory Update Reporting. National Chemical Information. 2,2-Dimethylbutane (75-83-2). Available from, as of October 3, 2013: https://cfpub.epa.gov/iursearch/index.cfm

8.5 General Manufacturing Information

EPA TSCA Commercial Activity Status
Butane, 2,2-dimethyl-: ACTIVE

8.6 Sampling Procedures

Charcoal tubes and passive vapor samples of organic chemicals including C5-C10 alkanes were taken in the field.
HICKEY J LS, BISHOP CC; AM IND HYG ASSOC J 42 (4): 264 (1981)
Stainless steel canister sampling method was compared with the tenax-GC adsorbent method in ambient atmosphere.
HOLDREN M ET AL; PROC ANNU MEET- AIR POLLUT CONTROL ASSOC 72ND (4): 79 (1979)

9 Identification

9.1 Analytic Laboratory Methods

Air samples were analyzed by GC using a cryogenic trapping technique for introduction of air samples into the gas chromatograph.
ALTWICKER ER, WHITBY RA; PROC ANNU MEET- AIR POLLUT CONTROL ASSOC 72ND (4): 79 (1979)
A modified variant of the purge-and-trap gas chromatographic analysis of volatile organic carbon compounds in water was designed. Samples collected in 1-1 glass bottles are purged at 60 °C for 1 hr in an ultrapure helium gas stream using an open loop arrangement. At a flow rate of 100 mg/min for 60 min, the method separated over 200 organic compounds within 40 min using flame ionization and ion trap detection and is capable of quantitation down to 5 ng/l per component. The recoveries of 2,2-dimethylbutane from water at 30 and 60 °C were 52 and 84%, respectively. Recoveries of 2,2-dimethylbutane with the two series of tubes (all Tenax-TA or 3 different kinds) were 33.7, 38.5, and 26.1%, and 33.0, 64.4, and 2.6% for tubes 1, 2, and 3, respectively. A specimen purge seawater standard chromatogram (Tenax-TA tube) revealed the presence of 2,2-dimethylbutane. 2,2-Dimethylbutane was also seen in chromatograms of water samples taken from Solent estuary in southern England.
Bianchi A et al; J Chromatogr 467 (1): 111-28 (1989)
The determination of volatile organic compounds /including 2,2-dimethylbutane/ from EPA method 524.2 using purge and trap capillary GC, ECD, and FID detection.
Kessels H et al; Analusis 20 (8): M55-60 (1992)

10 Safety and Hazards

10.1 Hazards Identification

10.1.1 GHS Classification

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Note
Pictograms displayed are for 99.8% (448 of 449) of reports that indicate hazard statements. This chemical does not meet GHS hazard criteria for 0.2% (1 of 449) of reports.
Pictogram(s)
Flammable
Irritant
Health Hazard
Environmental Hazard
Signal
Danger
GHS Hazard Statements

H225 (99.8%): Highly Flammable liquid and vapor [Danger Flammable liquids]

H304 (99.8%): May be fatal if swallowed and enters airways [Danger Aspiration hazard]

H315 (99.8%): Causes skin irritation [Warning Skin corrosion/irritation]

H319 (21.6%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]

H336 (99.1%): May cause drowsiness or dizziness [Warning Specific target organ toxicity, single exposure; Narcotic effects]

H411 (99.8%): Toxic to aquatic life with long lasting effects [Hazardous to the aquatic environment, long-term hazard]

Precautionary Statement Codes

P210, P233, P240, P241, P242, P243, P261, P264, P264+P265, P271, P273, P280, P301+P316, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P319, P321, P331, P332+P317, P337+P317, P362+P364, P370+P378, P391, P403+P233, P403+P235, P405, and P501

(The corresponding statement to each P-code can be found at the GHS Classification page.)

ECHA C&L Notifications Summary

Aggregated GHS information provided per 449 reports by companies from 19 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria per 1 of 449 reports by companies. For more detailed information, please visit ECHA C&L website.

There are 18 notifications provided by 448 of 449 reports by companies with hazard statement code(s).

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.

10.1.2 Hazard Classes and Categories

Flam. Liq. 2 (99.8%)

Asp. Tox. 1 (99.8%)

Skin Irrit. 2 (99.8%)

Eye Irrit. 2 (21.6%)

STOT SE 3 (99.1%)

Aquatic Chronic 2 (99.8%)

Flammable liquid - category 2

Aspiration hazard - category 1

Skin irritation - category 2

Specific target organ toxicity (single exposure) - category 3

Hazardous to the aquatic environment (chronic) - category 2

10.1.3 NFPA Hazard Classification

1 of 2
View All
NFPA 704 Diamond
2-3-0
NFPA Health Rating
2 - Materials that, under emergency conditions, can cause temporary incapacitation or residual injury.
NFPA Fire Rating
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.
NFPA Instability Rating
0 - Materials that in themselves are normally stable, even under fire conditions.

10.1.4 Health Hazards

Inhalation causes dizziness, nausea, and vomiting; concentrated vapor may cause unconsciousness and collapse. Contact with liquid causes irritation of eyes; repeated contact may produce irritation of skin. Ingestion causes irritation of stomach. Aspiration causes severe lung irritation, rapidly developing pulmonary edema, and central nervous system excitement followed by depression. (USCG, 1999)
U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
ERG 2024, Guide 128 (Neohexane)

CAUTION: Petroleum crude oil (UN1267) may contain TOXIC hydrogen sulphide gas.

· Inhalation or contact with material may irritate or burn skin and eyes.

· Fire may 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.

10.1.5 Fire Hazards

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]:

HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. 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 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. Containers may explode when heated. Many liquids will float on water. Substance may be transported hot. For hybrid vehicles, ERG Guide 147 (lithium ion or sodium ion batteries) or ERG Guide 138 (sodium batteries) should also be consulted. If molten aluminum is involved, refer to ERG Guide 169. (ERG, 2024)

ERG 2024, Guide 128 (Neohexane)

· HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.

· 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 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.

· Containers may explode when heated.

· Many liquids will float on water.

· Substance may be transported hot.

· For hybrid vehicles, GUIDE 147 (lithium ion or sodium ion batteries) or GUIDE 138 (sodium batteries) should also be consulted.

· If molten aluminum is involved, refer to GUIDE 169.

10.1.6 Hazards Summary

After exposure to hexane for 10 minutes, humans experience no effect at 2000 ppm and dizziness or giddiness at 5000 ppm. Like other solvents, hexane isomers are CNS depressants and cardiac sensitizers. Isomers other than n-hexane have the same TLV-TWA. These other isomers include 2,2-dimethylbutane, 2,3-dimethylbutane, 2-methyl pentane, and 3-methyl pentane. [ACGIH] Branched hexanes are less toxic than n-hexane. Cardiac sensitization occurs in dogs inhaling neohexane at 100,000-250,000 ppm. [CHEMINFO]
ACGIH - Documentation of the TLVs and BEIs, 7th Ed. Cincinnati: ACGIH Worldwide, 2020.

10.2 Safety and Hazard Properties

10.2.1 Flammable Limits

Lower flammable limit: 1.2% by volume; Upper flammable limit: 7.0% by volume.
National Fire Protection Association; Fire Protection Guide to Hazardous Materials. 14TH Edition, Quincy, MA 2010, p. 325-49

10.2.2 Lower Explosive Limit (LEL)

1.2 % (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
1.2%

10.2.3 Upper Explosive Limit (UEL)

7 % (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
7%

10.2.4 Critical Temperature & Pressure

Critical temperature: 498.1 K
Haynes, W.M. (ed.) CRC Handbook of Chemistry and Physics. 91st ed. Boca Raton, FL: CRC Press Inc., 2010-2011, p. 6-62

10.2.5 Explosive Limits and Potential

Explosion limits 1.2-7%
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 880

10.2.6 NIOSH Recommendations

Recommended Exposure Limits: 10 Hour Time-Weighted Average: 100 ppm (350 mg/cu m) /Hexane isomers (excluding n-Hexane)/
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg
Recommended Exposure Limits: 15 Minute Ceiling Value: 510 ppm (1800 mg/cu m) /Hexane isomers (excluding n-Hexane)/
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg

10.3 First Aid Measures

10.3.1 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.

SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment.

INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing.

INGESTION: DO NOT INDUCE VOMITING. Volatile chemicals have a high risk of being aspirated into the victim's lungs during vomiting which increases the medical problems. If the victim is conscious and not convulsing, give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison control center. IMMEDIATELY transport the victim to a hospital. If the victim is convulsing or unconscious, do not give anything by mouth, ensure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital. (NTP, 1992)

National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
ERG 2024, Guide 128 (Neohexane)

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 ingestedor 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).

-- If no pulse detected or no respiratory medical device available, provide continuouscompressions. Conduct a pulse check every two minutes or monitor for any signs of spontaneous respirations.

· Remove and isolate contaminated clothing and shoes.

· For minor skin contact, avoid spreading material on unaffected skin.

· In case of contact with substance, remove immediately by flushing skin or eyes with running water for at least 20 minutes.

· For severe burns, immediate medical attention is required.

· Effects of exposure (inhalation, ingestion, or skin contact) to substance may be delayed.

· Keep victim calm and warm.

· Keep victim under observation.

· For further assistance, contact your local Poison Control Center.

· Note: Basic Life Support (BLS) and Advanced Life Support (ALS) should be done by trained professionals.

Specific First Aid:

· Wash skin with soap and water.

· In case of burns, immediately cool affected skin for as long as possible with cold water. Do not remove clothing if adhering to skin.

In Canada, an Emergency Response Assistance Plan (ERAP) may be required for this product. Please consult the shipping paper and/or the "ERAP" section.

10.4 Fire Fighting

Fire Extinguishing Agents Not to Be Used: Water may be ineffective.

Fire Extinguishing Agents: Dry chemical, foam, carbon dioxide (USCG, 1999)

U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.

10.4.1 Fire Fighting Procedures

Wear self contained breathing apparatus for fire fighting if necessary.
Sigma-Aldrich Material Safety Data Sheet for 2,2-Dimethylbutane. Product number 39730. Version 3.7 (November 9, 2012). Available from, as of September 25, 2013. https://www.sigmaaldrich.com/catalog/product/fluka/39730?lang=en&region=us
Use water spray to cool unopened containers.
Sigma-Aldrich Material Safety Data Sheet for 2,2-Dimethylbutane. Product number 39730. Version 3.7 (November 9, 2012). Available from, as of September 25, 2013. https://www.sigmaaldrich.com/catalog/product/fluka/39730?lang=en&region=us
Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.
Sigma-Aldrich Material Safety Data Sheet for 2,2-Dimethylbutane. Product number 39730. Version 3.7 (November 9, 2012). Available from, as of September 25, 2013. https://www.sigmaaldrich.com/catalog/product/fluka/39730?lang=en&region=us

10.5 Accidental Release Measures

Public Safety: ERG 2024, Guide 128 (Neohexane)

· 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.

· Keep unauthorized personnel away.

· Stay upwind, uphill and/or upstream.

· Ventilate closed spaces before entering, but only if properly trained and equipped.

Spill or Leak: ERG 2024, Guide 128 (Neohexane)

· ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area.

· All equipment used when handling the product must be grounded.

· Do not touch or walk through spilled material.

· Stop leak if you can do it without risk.

· Prevent entry into waterways, sewers, basements or confined areas.

· A vapor-suppressing foam may be used to reduce vapors.

· Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers.

· Use clean, non-sparking tools to collect absorbed material.

Large Spill

· Dike far ahead of liquid spill for later disposal.

· Water spray may reduce vapor, but may not prevent ignition in closed spaces.

10.5.1 Isolation and Evacuation

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area for at least 50 meters (150 feet) in all directions.

LARGE SPILL: Consider initial downwind evacuation for at least 300 meters (1000 feet).

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)

Evacuation: ERG 2024, Guide 128 (Neohexane)

Immediate precautionary measure

· Isolate spill or leak area for at least 50 meters (150 feet) in all directions.

Large Spill

· Consider initial downwind evacuation for at least 300 meters (1000 feet).

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.

10.5.2 Cleanup Methods

Contain spillage, and then collect with an electrically protected vacuum cleaner or by wet-brushing and place in container for disposal according to local regulations...
Sigma-Aldrich Material Safety Data Sheet for 2,2-Dimethylbutane. Product number 39730. Version 3.7 (November 9, 2012). Available from, as of September 25, 2013. https://www.sigmaaldrich.com/catalog/product/fluka/39730?lang=en&region=us

10.5.3 Disposal Methods

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. If it is not practicable to manage the chemical in this fashion, it must be evaluated in accordance with EPA 40 CFR Part 261, specifically Subpart B, in order to determine the appropriate local, state and federal requirements for disposal.
Burn in a chemical incinerator equipped with an afterburner and scrubber but exert extra care in igniting as this material is highly flammable. Offer surplus and non-recyclable solutions to a licensed disposal company. Contact a licensed professional waste disposal service to dispose of this material.
Sigma-Aldrich Material Safety Data Sheet for 2,2-Dimethylbutane. Product number 39730. Version 3.7 (November 9, 2012). Available from, as of September 25, 2013. https://www.sigmaaldrich.com/catalog/product/fluka/39730?lang=en&region=us

10.5.4 Preventive Measures

SRP: Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. The completeness of the cleaning procedures should be considered before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at the end of shift, but should remain at employee's place of work for cleaning.
Use personal protective equipment. 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.
Sigma-Aldrich Material Safety Data Sheet for 2,2-Dimethylbutane. Product number 39730. Version 3.7 (November 9, 2012). Available from, as of September 25, 2013. https://www.sigmaaldrich.com/catalog/product/fluka/39730?lang=en&region=us
The worker should immediately wash the skin when it becomes contaminated. /Hexane isomers (excluding n-Hexane)/
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg
Work clothing that becomes wet should be immediately removed due to it flammability hazard (i.e., for liquids with a flash point <100 def F). /Hexane isomers (excluding n-Hexane)/
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg

10.6 Handling and Storage

10.6.1 Nonfire Spill Response

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. All equipment used when handling the product must be grounded. Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. A vapor-suppressing foam may be used to reduce vapors. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. Use clean, non-sparking tools to collect absorbed material.

LARGE SPILL: Dike far ahead of liquid spill for later disposal. Water spray may reduce vapor, but may not prevent ignition in closed spaces. (ERG, 2024)

10.6.2 Storage Conditions

Over time, pressure may increase causing containers to burst. Handle and open container with care. Moisture sensitive.
Sigma-Aldrich Material Safety Data Sheet for 2,2-Dimethylbutane. Product number 39730. Version 3.7 (November 9, 2012). Available from, as of September 25, 2013. https://www.sigmaaldrich.com/catalog/product/fluka/39730?lang=en&region=us
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.
Sigma-Aldrich Material Safety Data Sheet for 2,2-Dimethylbutane. Product number 39730. Version 3.7 (November 9, 2012). Available from, as of September 25, 2013. https://www.sigmaaldrich.com/catalog/product/fluka/39730?lang=en&region=us
...Use explosion-proof equipment. Keep away from sources of ignition - No smoking. Take measures to prevent the build up of electrostatic charge.
Sigma-Aldrich Material Safety Data Sheet for 2,2-Dimethylbutane. Product number 39730. Version 3.7 (November 9, 2012). Available from, as of September 25, 2013. https://www.sigmaaldrich.com/catalog/product/fluka/39730?lang=en&region=us

10.7 Exposure Control and Personal Protection

Protective Clothing: ERG 2024, Guide 128 (Neohexane)

· Wear positive pressure self-contained breathing apparatus (SCBA).

· Structural firefighters' protective clothing provides thermal protection but only limited chemical protection.

Maximum Allowable Concentration (MAK)
500.0 [ppm]

10.7.2 Threshold Limit Values (TLV)

200.0 [ppm]
8 hr Time Weighted Avg (TWA): 500 ppm; 15 min Short Term Exposure Limit (STEL): 1000 ppm.
American Conference of Governmental Industrial Hygienists. Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices. ACGIH, Cincinnati, OH 2014, p. 34
TLV-TWA (Time Weighted Average)
500 ppm [1979]
TLV-STEL (Short Term Exposure Limit)
1000 ppm [1979]

10.7.3 Emergency Response Planning Guidelines

Emergency Response: ERG 2024, Guide 128 (Neohexane)

CAUTION: The majority of these products have a very low flash point. Use of water spray when fighting fire may be inefficient.

CAUTION: For mixtures containing alcohol or polar solvent, alcohol-resistant foam may be more effective.

Small Fire

· Dry chemical, CO2, water spray or regular foam. If regular foam is ineffective or unavailable, use alcohol-resistant foam.

Large Fire

· Water spray, fog or regular foam. If regular foam is ineffective or unavailable, use alcohol-resistant foam.

· Avoid aiming straight or solid streams directly onto the product.

· If it can be done safely, move undamaged containers away from the area around the fire.

Fire Involving Tanks, Rail Tank Cars or Highway Tanks

· Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles.

· Cool containers with flooding quantities of water until well after fire is out.

· For petroleum crude oil, do not spray water directly into a breached tank car. This can lead to a dangerous boil over.

· Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank.

· ALWAYS stay away from tanks in direct contact with flames.

· For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn.

10.7.4 Personal Protective Equipment (PPE)

Air-supplied apparatus or organic vapor cartridge; goggles or face shield; rubber gloves. (USCG, 1999)
U.S. Coast Guard. 1999. Chemical Hazard Response Information System (CHRIS) - Hazardous Chemical Data. Commandant Instruction 16465.12C. Washington, D.C.: U.S. Government Printing Office.
Where risk assessment shows air-purifying respirators are appropriate use of full-face respirator with multi-purpose combination (US) or type AXBEK (EN 14387) respirator cartridges as a backup to engineering controls. If the respirator is the sole means of protection, use a full-face supplied air respirator. Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU).
Sigma-Aldrich Material Safety Data Sheet for 2,2-Dimethylbutane. Product number 39730. Version 3.7 (November 9, 2012). Available from, as of September 25, 2013. https://www.sigmaaldrich.com/catalog/product/fluka/39730?lang=en&region=us
Handle with gloves...
Sigma-Aldrich Material Safety Data Sheet for 2,2-Dimethylbutane. Product number 39730. Version 3.7 (November 9, 2012). Available from, as of September 25, 2013. https://www.sigmaaldrich.com/catalog/product/fluka/39730?lang=en&region=us
Respirator Recommendations: Up to 1000 ppm: /Hexane isomers (excluding n-Hexane)/
Assigned Protection Factor (APF)
APF = 10
Respirator Recommendations
Any supplied-air respirator. Substance reported to cause eye irritation or damage; may require eye protection.
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg
Respirator Recommendations: Up to 2500 ppm: /Hexane isomers (excluding n-Hexane)/
Assigned Protection Factor (APF)
APF = 25
Respirator Recommendations
Any supplied-air respirator operated in a continuous-flow mode. Substance reported to cause eye irritation or damage; may require eye protection.
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg
For more Personal Protective Equipment (PPE) (Complete) data for 2,2-DIMETHYLBUTANE (9 total), please visit the HSDB record page.

10.8 Stability and Reactivity

10.8.1 Air and Water Reactions

Highly flammable. Insoluble in water.

10.8.2 Reactive Group

Hydrocarbons, Aliphatic Saturated

10.8.3 Reactivity Alerts

Highly Flammable

10.8.4 Reactivity Profile

NEOHEXANE may be incompatible with strong oxidizing agents like nitric acid. Charring may occur followed by ignition of unreacted material and other nearby combustibles. In other settings, mostly unreactive. Not affected by aqueous solutions of acids, alkalis, most oxidizing agents, and most reducing agents. When heated sufficiently or when ignited in the presence of air, oxygen or strong oxidizing agents, burns exothermically to produce carbon dioxide and water.

10.8.5 Hazardous Reactivities and Incompatibilities

Oxidizing agents
Sigma-Aldrich Material Safety Data Sheet for 2,2-Dimethylbutane. Product number 39730. Version 3.7 (November 9, 2012). Available from, as of September 25, 2013. https://www.sigmaaldrich.com/catalog/product/fluka/39730?lang=en&region=us

10.9 Transport Information

10.9.1 DOT Emergency Guidelines

/GUIDE 128: FLAMMABLE LIQUIDS (NON-POLAR/WATER-IMMISCIBLE)/ Fire or Explosion: HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. 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 ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion 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. Containers may explode when heated. Many liquids are lighter than water. Substances may be transported hot. /Hexanes/
U.S. Department of Transportation. 2012 Emergency Response Guidebook. Washington, D.C. 2012
/GUIDE 128: FLAMMABLE LIQUIDS (NON-POLAR/WATER-IMMISCIBLE)/ Health: Inhalation or contact with material may irritate or burn skin and eyes. Fire may produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control or dilution water may cause pollution. /Hexanes/
U.S. Department of Transportation. 2012 Emergency Response Guidebook. Washington, D.C. 2012
/GUIDE 128: FLAMMABLE LIQUIDS (NON-POLAR/WATER-IMMISCIBLE)/ Public Safety: CALL Emergency Response Telephone Number ... As an immediate precautionary measure, isolate spill or leak area for at least 50 meters (150 feet) in all directions. Keep unauthorized personnel away. Stay upwind. Keep out of low areas. Ventilate closed spaces before entering. /Hexanes/
U.S. Department of Transportation. 2012 Emergency Response Guidebook. Washington, D.C. 2012
/GUIDE 128: FLAMMABLE LIQUIDS (NON-POLAR/WATER-IMMISCIBLE)/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Structural firefighters' protective clothing will only provide limited protection. /Hexanes/
U.S. Department of Transportation. 2012 Emergency Response Guidebook. Washington, D.C. 2012
For more DOT Emergency Guidelines (Complete) data for 2,2-DIMETHYLBUTANE (8 total), please visit the HSDB record page.

10.9.2 Shipping Name / Number DOT/UN/NA/IMO

UN 1208; Hexanes
IMO 3.1; Hexanes

10.9.3 Shipment Methods and Regulations

No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that person is registered in conformance ... and the hazardous material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./
49 CFR 171.2 (USDOT); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of November 4, 2013: https://www.ecfr.gov/cgi-bin/ECFR?page=browse
The International Air Transport Association (IATA) Dangerous Goods Regulations are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and constitute a manual of industry carrier regulations to be followed by all IATA Member airlines when transporting hazardous materials.
International Air Transport Association. Dangerous Goods Regulations. 47th Edition. Montreal, Quebec Canada. 2006., p. 200
The International Maritime Dangerous Goods Code lays down basic principles for transporting hazardous chemicals. Detailed recommendations for individual substances and a number of recommendations for good practice are included in the classes dealing with such substances. A general index of technical names has also been compiled. This index should always be consulted when attempting to locate the appropriate procedures to be used when shipping any substance or article.
International Maritime Organization. IMDG Code. International Maritime Dangerous Goods Code Volume 2 2006, p. 51

10.9.4 DOT Label

Flammable Liquid

10.10 Regulatory Information

The Australian Inventory of Industrial Chemicals
Chemical: Butane, 2,2-dimethyl-
REACH Registered Substance
New Zealand EPA Inventory of Chemical Status
2,2-Dimethyl-butane: Does not have an individual approval but may be used under an appropriate group standard

10.11 Other Safety Information

10.11.1 Toxic Combustion Products

Hazardous decomposition products formed under fire conditions. -Carbon oxides.
Sigma-Aldrich Material Safety Data Sheet for 2,2-Dimethylbutane. Product number 39730. Version 3.7 (November 9, 2012). Available from, as of September 25, 2013. https://www.sigmaaldrich.com/catalog/product/fluka/39730?lang=en&region=us

11 Toxicity

11.1 Toxicological Information

11.1.1 Toxicity Summary

Hexane's toxicity is caused by it neurotoxic metabolite, 2,5-hexanedione. It damages the central and peripheral nervous system by causing axonal swelling and degeneration. 2,5-Hexanedione also reacts with lysine side-chain amino groups in axonal cytoskeletal proteins to form pyrroles. This results in neurofilament cross-linking and loss of function. (L175)
L175: Wikipedia. Methanol. Last Updated 19 May 2009. http://en.wikipedia.org/wiki/Methanol

11.1.2 Carcinogen Classification

Carcinogen Classification
2,2-Dimethylbutane is found in gasoline, which is possibly carcinogenic to humans (Group 2B). (L135)

11.1.3 Health Effects

Hexane mainly affects the nervous system. It causes degeneration of the peripheral nervous system (and eventually the central nervous system), starting with damage to the nerve axons. Exposure to hexane may also damage the lungs and reproductive system. (L977, L978)
L977: Wikipedia. Hexane. Last Updated 15 June 2009. http://en.wikipedia.org/wiki/Hexane
L978: ATSDR - Agency for Toxic Substances and Disease Registry (1999). Toxicological profile for n-hexane. U.S. Public Health Service in collaboration with U.S. Environmental Protection Agency (EPA). http://www.atsdr.cdc.gov/toxprofiles/tp113.html

11.1.4 Exposure Routes

Oral (L175) ;inhalation (L175) ;dermal (L175)
L175: Wikipedia. Methanol. Last Updated 19 May 2009. http://en.wikipedia.org/wiki/Methanol

11.1.5 Symptoms

Breathing large amounts of hexane causes numbness in the feet and hands, followed by muscle weakness in the feet and lower legs. Continued exposure may lead to paralysis of the arms and legs. However, if removed from the exposure, recovery occurs in 6 months to a year. Inhalation of high concentrations produces first a state of mild euphoria, followed by somnolence with headaches and nausea. (L175, A121)
A121: Meulenberg CJ, Vijverberg HP: Selective inhibition of gamma-aminobutyric acid type A receptors in human IMR-32 cells by low concentrations of toluene. Toxicology. 2003 Aug 28;190(3):243-8. PMID:12927378
L175: Wikipedia. Methanol. Last Updated 19 May 2009. http://en.wikipedia.org/wiki/Methanol

11.1.6 Adverse Effects

Neurotoxin - Acute solvent syndrome

ACGIH Carcinogen - Confirmed Animal.

11.1.7 Minimum Risk Level

Chronic Inhalation: 0.6 ppm (L134)
L134: ATSDR - Agency for Toxic Substances and Disease Registry (2001). Minimal Risk Levels (MRLs) for Hazardous Substances. U.S. Public Health Service in collaboration with U.S. Environmental Protection Agency (EPA). http://www.atsdr.cdc.gov/mrls/

11.1.8 Antidote and Emergency Treatment

Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR if necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on the left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Aliphatic hydrocarbons and related compounds/
Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3Rd edition, Elsevier Mosby, St. Louis, MO 2005, p. 241
Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 mL/kg up to 200 mL of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool. Administer activated charcoal ... . Treat frostbite with rapid rewarming techniques ... ./Aliphatic hydrocarbons and related compounds/
Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3Rd edition, Elsevier Mosby, St. Louis, MO 2005, p. 241-2
Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Positive-pressure ventilation techniques with a bag-valve-mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's (LR) if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously.Watch for signs of fluid overload ... . Treat seizures with diazepam or lorazepam ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Aliphatic hydrocarbons and related compounds/
Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3Rd edition, Elsevier Mosby, St. Louis, MO 2005, p. 242

11.1.9 Non-Human Toxicity Excerpts

/OTHER TOXICITY INFORMATION/ ... 2,2-Dimethylbutane at conc of 100,000-250,000 ppm sensitizes the myocardium in dogs to epinephrine-induced cardiac arrhythmias.
Snyder, R. (ed.) Ethel Browning's Toxicity and Metabolism of Industrial Solvents. 2nd ed. Volume 1: Hydrocarbons. Amsterdam - New York - Oxford: Elsevier, 1987., p. 295

11.2 Ecological Information

11.2.1 Environmental Fate / Exposure Summary

2,2-Dimethylbutane's production and use as an intermediate for agricultural chemicals and as a component of high-octane motor and aviation fuels may result in its release to the environment through various waste streams. If released to air, a vapor pressure of 319 mm Hg at 25 °C indicates 2,2-dimethylbutane will exist solely as a vapor in the atmosphere. Vapor-phase 2,2-dimethylbutane will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 7 days. 2,2-Dimethylbutane does not contain chromophores that absorb at wavelengths >290 nm and, therefore, is not expected to be susceptible to direct photolysis by sunlight. If released to soil, 2,2-dimethylbutane is expected to have slight mobility based upon an estimated Koc of 2100. Volatilization from moist soil surfaces is expected to be an important fate process based upon an estimated Henry's Law constant of 1.7 atm-cu m/mole. 2,2-Dimethylbutane may volatilize from dry soil surfaces based upon its vapor pressure. Under aerobic conditions, 2,2-dimethylbutane was shown to degrade after a 15 day lag period when tested as a mixture of light hydrocarbons in activated sludge (14% of the initial amount remained after 34 days of incubation); however, when tested as the single carbon source little degradation was observed (86% of the initial amount remained) suggesting that biodegradation may occur via co-metabolism. If released into water, 2,2-dimethylbutane is expected to adsorb to suspended solids and sediment based upon the estimated Koc. Volatilization from water surfaces is expected to be an important fate process based upon this compound's estimated Henry's Law constant. Estimated volatilization half-lives for a model river and model lake are 57 minutes and 3.7 days, respectively. An estimated BCF of 150 suggests bioconcentration in aquatic organisms is high. Hydrolysis is not expected to be an important environmental fate process since this compound lacks functional groups that hydrolyze under environmental conditions (pH 5 to 9). Occupational exposure to 2,2-dimethylbutane may occur through inhalation and dermal contact with this compound at workplaces where 2,2-dimethylbutane is produced or used. 2,2-Dimethylbutane is widely detected in vehicle exhaust and gasoline vapors. Monitoring data indicate that the general population may be exposed to 2,2-dimethylbutane via inhalation of ambient air, and as a result of handling gasoline. (SRC)

11.2.2 Artificial Pollution Sources

2,2-Dimethylbutane's production and use as an intermediate for agricultural chemicals and as a component of high-octane motor and aviation fuels(1) may result in its release to the environment through various waste streams(SRC).
(1) Lewis RJ Sr; Hawley's Condensed Chemical Dictionary. 15th ed. New York, NY: John Wiley & Sons, Inc p. 880 (2007)

11.2.3 Environmental Fate

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 2100(SRC), determined from a log Kow of 3.82(2) and a regression-derived equation(3), indicates that 2,2-dimethylbutane is expected to have slight mobility in soil(SRC). Volatilization of 2,2-dimethylbutane from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 1.7 atm-cu m/mole(SRC) derived from its vapor pressure, 319 mm Hg(4), and water solubility, 21.2 mg/L(5). 2,2-Dimethylbutane is expected to volatilize from dry soil surfaces(SRC) based upon it's vapor pressure of 319 mm Hg at 25 °C(4). Under aerobic conditions, 2,2-dimethylbutane was shown to degrade after a 15 day lag period when tested as a mixture of light hydrocarbons in activated sludge (14% of the initial amount remained after 34 days of incubation); however, when tested as the single carbon source little degradation was observed (86% of the initial amount remained) suggesting that biodegradation may occur via co-metabolism(6).
(1) Swann RL et al; Res Rev 85: 17-28 (1983)
(2) Hansch C et al; Exploring QSAR. Hydrophobic, Electronic, and Steric Constants. ACS Prof Ref Book. Heller SR, consult. ed., Washington, DC: Amer Chem Soc p. 24 (1995)
(3) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.1. Nov, 2012. Available from, as of Oct 8, 2013: https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
(4) Boublik T et al; The Vapour Pressures of Pure Substances. 2nd rev ed. Amsterdam: Elsevier, (1984)
(5) Yalkowsky SH, He Y, eds; Handbook of aqueous solubility data. Boca Raton, FL: CRC Press p. 319 (2003)
(6) Solano-Serena F et al; Appl Microbiol Biotechnol 54: 121-5 (2000)
AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 2100(SRC), determined from a log Kow of 3.82(2) and a regression-derived equation(3), indicates that 2,2-dimethylbutane is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(4) based upon an estimated Henry's Law constant of 1.7 atm-cu m/mole(SRC), derived from its vapor pressure, 319 mm Hg(5), and water solubility, 2.12 mg/L(6). Using this Henry's Law constant and an estimation method(7), volatilization half-lives for a model river and model lake are 57 minutes and 3.7 days, respectively(SRC). According to a classification scheme(8), an estimated BCF of 150(SRC), from its log Kow(2) and a regression-derived equation(3), suggests the potential for bioconcentration in aquatic organisms is high(SRC). Under aerobic conditions, 2,2-dimethylbutane was shown to degrade after a 15 day lag period when tested as a mixture of light hydrocarbons in activated sludge (14% of the initial amount remained after 34 days of incubation); however, when tested as the single carbon source little degradation was observed (86% of the initial amount remained) suggesting that biodegradation may occur via co-metabolism(9).
(1) Swann RL et al; Res Rev 85: 17-28 (1983)
(2) Hansch C et al; Exploring QSAR. Hydrophobic, Electronic, and Steric Constants. ACS Prof Ref Book. Heller SR, consult. ed., Washington, DC: Amer Chem Soc p. 24 (1995)
(3) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.1. Nov, 2012. Available from, as of October 8, 2013: https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
(4) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 15-1 to 15-29 (1990)
(5) Boublik T et al; The Vapour Pressures of Pure Substances. 2nd rev ed. Amsterdam: Elsevier, (1984)
(6) Yalkowsky SH, He Y, eds; Handbook of aqueous solubility data. Boca Raton, FL: CRC Press p. 319 (2003)
(7) Meylan WM, Howard PH; Environ Toxicol Chem 10: 1283-93 (1991)
(8) Franke C et al; Chemosphere 29: 1501-14 (1994)
(9) Solano-Serena F et al; Appl Microbiol Biotechnol 54: 121-5 (2000)
ATMOSPHERIC FATE: 2,2,-Dimethylbutane, which has a vapor pressure of 319 mm Hg at 25 °C(1), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 2,2-dimethylbutane 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 7 days(2), calculated from its rate constant of 2.32X10-12 cu cm/molecule-sec at 25 °C(3). 2,2-Dimethylbutane 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).
(1) Boublik T et al; The Vapour Pressures of Pure Substances. 2nd rev ed. Amsterdam: Elsevier, (1984)
(2) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.1. Nov, 2012. Available from, as of Oct 9, 2013: https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
(3) Atkinson R; J Phys Chem Ref Data Monograph No. 1 (1989)
(4) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 8-12 (1990)

11.2.4 Environmental Biodegradation

AEROBIC: Under aerobic conditions, 2,2-dimethylbutane was shown to degrade after a 15 day lag period when tested as a mixture of light hydrocarbons in activated sludge (14% of the initial amount remained after 34 days of incubation). However, when tested as the single carbon source little degradation was observed (86% of the initial amount remained; comparable to the abiotic control where 89% remained) suggesting that its degradation may occur via co-metabolism(1). In another aerobic biodegradation study of gasoline hydrocarbons in water from a domestic sewage treatment plant, a degradation half-life for 2,2-dimethylbutane was calculated as 26.5 days(2). Under optimal conditions, biodegradation results for gasoline in activated sludge indicate that 2,2-dimethylbutane constituted a recalcitrant portion of the mixture(3).
(1) Solano-Serena F et al; Appl Microbiol Biotechnol 54: 121-5(2000)
(2) Prince RC et al; Environ Sci Technol 41: 3316-3321 (2007)
(3) Marchal R et al; Oil Gas Sci. Technol: 58: 441-448 (2003)
AEROBIC: Incubation with natural flora in the groundwater - in presence of the other components of high-octane gasoline (100 uL/L): biodegradation: 25% after 192 hr at 13 °C (initial concentration 0.28 uL/L).
Verschueren, K. Handbook of Environmental Data on Organic Chemicals. Volumes 1-2. 4th ed. John Wiley & Sons. New York, NY. 2001, p. 904
PURE CULTURE: Using the Clark oxygen electrode, a resting cell suspension of Corynebacterium sp. oxidized 2,2-dimethylbutane with an activity of 41% that of n-octane; the study indicated that the compound was utilized as a growth substrate by the microorganism(1). Therefore, this compound may have the potential to biodegrade, but is not expected to biodegrade rapidly(SRC).
(1) Buswell JA, Jurtshuk P; Arch Mikrobiol 64: 215-22 (1969)

11.2.5 Environmental Abiotic Degradation

The rate constant for the vapor-phase reaction of 2,2-dimethylbutane with photochemically-produced hydroxyl radicals has been reported as 2.32X10-12 cu cm/molecule-sec at 25 °C(1). This corresponds to an atmospheric half-life of about 7 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(2). 2,2-Dimethylbutane is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(3). 2,2-Dimethylbutane does not contain chromophores that absorb at wavelengths >290 nm(3) and, therefore, is not expected to be susceptible to direct photolysis by sunlight(SRC).
(1) Atkinson R; J Phys Chem Ref Data Monograph No. 1 (1989)
(2) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.1. Nov, 2012. Available from, as of Oct 9, 2013: https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
(3) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 7-4, 7-5, 8-12 (1990)

11.2.6 Environmental Bioconcentration

An estimated BCF of 150 was calculated in fish for 2,2-dimethylbutane(SRC), using a log Kow of 3.82(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is high(SRC), provided the compound is not metabolized by the organism(SRC).
(1) Hansch C et al; Exploring QSAR. Hydrophobic, Electronic, and Steric Constants. ACS Prof Ref Book. Heller SR, consult. ed., Washington, DC: Amer Chem Soc p. 24 (1995)
(2) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.1. Nov, 2012. Available from, as of October 9, 2013: https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
(3) Franke C et al; Chemosphere 29: 1501-14 (1994)

11.2.7 Soil Adsorption / Mobility

The Koc of 2,2-dimethylbutane is estimated as 2100(SRC), using a log Kow of 3.82(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that 2,2-dimethylbutane is expected to have slight mobility in soil.
(1) Hansch C et al; Exploring QSAR. Hydrophobic, Electronic, and Steric Constants. ACS Prof Ref Book. Heller SR, consult. ed., Washington, DC: Amer Chem Soc p. nn (1995)
(2) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.1. Nov, 2012. Available from, as of October 9, 2013: https://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
(3) Swann RL et al; Res Rev 85: 17-28 (1983)

11.2.8 Volatilization from Water / Soil

The Henry's Law constant for 2,2-dimethylbutane is estimated as 1.7 atm-cu m/mole(SRC) derived from its vapor pressure, 319 mm Hg(1), and water solubility, 21.2 mg/L (2). This Henry's Law constant indicates that 2,2-dimethylbutane is expected to volatilize rapidly from water surfaces(3). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(3) is estimated as 57 minutes(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(3) is estimated as 3.7 days(SRC). 2,2-Dimethylbutane's estimated Henry's Law constant indicates that volatilization from moist soil surfaces may occur(SRC). The potential for volatilization of 2,2-dimethylbutane from dry soil surfaces may exist (SRC) based upon a vapor pressure of 319 mm Hg(1).
(1) Boublik T et al; The Vapour Pressures of Pure Substances. 2nd rev ed. Amsterdam: Elsevier, (1984)
(2) Yalkowsky SH, He Y, eds; Handbook of aqueous solubility data. Boca Raton, FL: CRC Press p. 319 (2003)
(3) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 15-1 to 15-29 (1990)

11.2.9 Environmental Water Concentrations

SURFACE WATER: 2,2-Dimethylbutane was measured in eight samples of sea water taken during a cruise on the Indian Ocean; concentrations ranged from 0.24-1.91 nanoliters of vapor per liter of water at approximately 30 °C(1).
(1) Bonsang B et al; J Atmos Chem 6: 3-20 (1988)

11.2.10 Effluent Concentrations

In Southern California, the 2,2-dimethylbutane profile for various emissions for vehicle exhaust was 0.44, 0.35, 1.01, 0.00, 0.85, and 1.73 wt% for: an EPA 46 car study, mean composite of 13 samples from the Caldecott Tunnel, cold start, stabilized, hot start, and from an older fleet, respectively(1). The average concentration of 2,2-dimethylbutane in the exhaust of 6 cars in the UK, 1988, was 1733 ppb(2). Gasoline engine exhaust (noncatalyst and catalyst equipped), and unburned gasoline (whole and headspace vapors) profiles include 2,2-dimethylbutane at concentrations of 0.3, 0.6, 0.2, and 0.3 wt%, respectively(3). Source composition profiles for exhaust from an FTP test of 46 in-use passenger vehicles for 1975-1982 model years, Vancouver gasoline, Vancouver gasoline vapor, Whatcom County gasoline and Whatcom County gasoline vapor included 2,2-dimethylbutane at 0.440, 0.218, 0.334, 0.192, 0.345% NMHC (non-methane hydrocarbons)(4). Emission rates of 2,2-dimethylbutane from light-duty and heavy-duty vehicles in the Fort McHenry tunnel(Baltimore, MD; collected June 1992) were measured as 4.5 and 15.9 mg/vehicle-mile, respectively; air concentrations at the east portal ranged from 1.9 to 67.8 ppbC. Emission rates of 2,2-dimethylbutane from light-duty and heavy-duty vehicles in the Tuscarora tunnel (Pennsylvania; collected September 1992) were measured as 2.3 and 12.1 mg/vehicle-mile, respectively; air concentrations ranged from 9.4 to 2.1 ppbC (5). 2,2-Dimethylbutane was emitted from the tailpipe of automobiles at a rate of 800 ug 2,2-dimethylbutane per kilometer (vehicles equipped with catalytic converters) and 195,000 ug 2,2-dimethylbutane per kilometer (vehicles without catalytic converters)(6). Vehicle emissions were analyzed in the Maria Maluf Tunnel in Sao Paulo, Brazil in May 2004. Average emission factors for 2,2-dimethylbutane were reported; May 5 morning, 10.2 mg/kg; May 5 evening, 16.4 mg/kg; May 6 morning, 122.9 mg/kg; May 6 evening, 26.2 mg/kg(7).
(1) Fujita EM et al; Environ Sci Technol 28:1633-49 (1994)
(2) Blake NL et al; J Geophys Res Atmos: 98D: 2851-64 (1993)
(3) Harley RA et al; Environ Sci Technol 26: 2395-408 (1992)
(4) McLaren R et al; Environ Sci Technol 30: 3001-3009 (1996)
(5) Zielinska B et al; Atmos Environ 30: 2269-86 (1996)
(6) Schauer JJ et al. Environ Sci Technol 36: 1169-1180 (2002)
(7) Martins LD et al; Environ Sci Technol 40: 6722-6729 (2006)

11.2.11 Atmospheric Concentrations

URBAN/SUBURBAN: The 2,2-dimethylbutane concentration ranged from 0 to 1 ppbV at a downtown Los Angeles location where it was detected in 4 of 17 samples in the Fall of 1981(1). The average concentration of 2,2-dimethylbutane at street level in London, 1988, was 16 ppb(2). The average and range of concentrations of 2,2-dimethylbutane measured in southern California over September 8-9, 1993 were 0.90 and 0.00-2.30 ug/cu m, respectively(3). 2,2-dimethylbutane has been detected in roadway air, airport facility air, and 'near' aircraft air in concentrations of 0.495, 0.50, and 0.172 ppb, respectively(4). 2,2-Dimethylbutane was detected at a mean concentration of 0.8 mg/cu m in the atmosphere of Porto Alegre, Brazil from March 1996 to April 1997(5). The arithmetic and geometric means were 47.9 and 43.9 ppbC, respectively, for the atmospheric 2,2-dimethylbutane content at urban locations in NW England(6). 2,2-dimethylbutane was detected at a mean concentration of 1.1 ug/cu m around the Los Angeles, CA area during a smog event on September 8-9, 1993(7).
(1) Grosjean D, Fung K; J Air Pollut Control Assoc. 34:537-43 (1984)
(2) Blake NJ et al; J. Geophys Res Atmos: 98D: 2851-64 (1993)
(3) Fraser MP, et al; Environ Sci Technol 31: 2356-67 (1997)
(4) Conner TL et al; J Air Waste Manage Assoc 45: 383-94 (1995)
(5) Grosjean E et al; Environ Sci Technol 32: 2061-9 (1998)
(6) Colbeck I, Harrison RM; Atmos Environ 19: 1899-904 (1985)
(7) Fraser MP et al; Environ Sci Technol 34: 1302-12 (2000)
RURAL/REMOTE: For the atmospheric 2,2-dimethylbutane content at rural locations in NW England, the arithmetic and geometric means were 1.8 and 1.8 ppbC, respectively(1).
(1) Colbeck I, Harrison RM; Atmos Environ 19: 1899-904 (1985)
SOURCE DOMINATED: In oil field emissions measured in Tulsa, OK, 2,2-dimethylbutane was detected at average concentration of 7.0 ppbC(1). The arithmetic and geometric means were 11.2 and 4.4 ppbC, respectively, for the atmospheric 2,2-dimethylbutane content at polluted rural locations in northwest England(2). 2,2-Dimethylbutane was detected in air samples collected in June 2004 from a gasoline service station located in Brazil at an average concentration of 19.5 ug/cu m(3).
(1) Viswanath RS; J Air Waste Manage Assoc 44: 989-94 (1994)
(2) Colbeck I, Harrison RM; Atmos Environ 19: 1899-904 (1985)
(3) Deoliveira KMPG; Bull Environ Contam Toxicol 79: 237-241 (2007)

11.2.12 Probable Routes of Human Exposure

According to the 2006 TSCA Inventory Update Reporting data, the number of persons reasonably likely to be exposed in the industrial manufacturing, processing, and use of 2,2-dimethylbutane is 1 to 99; the data may be greatly underestimated(1).
(1) US EPA; Inventory Update Reporting (IUR). Nonconfidential 2006 IUR Records by Chemical, including Manufacturing, Processing and Use Information. Washington, DC: U.S. Environmental Protection Agency. Available from, as of Oct 9, 2013: https://cfpub.epa.gov/iursearch/index.cfm
Occupational exposure to 2,2-dimethylbutane may occur through inhalation and dermal contact with this compound at workplaces where 2,2-dimethylbutane is produced or used. 2,2-Dimethylbutane is widely detected in vehicle exhaust and gasoline vapors. Monitoring data indicate that the general population may be exposed to 2,2-dimethylbutane via inhalation of ambient air, and as a result of handling gasoline. (SRC)

12 Associated Disorders and Diseases

Associated Occupational Diseases with Exposure to the Compound
Solvents, acute toxic effect [Category: Acute Poisoning]

13 Literature

13.1 Consolidated References

13.2 Springer Nature References

13.3 Thieme References

13.4 Wiley References

13.5 Nature Journal References

13.6 Chemical Co-Occurrences in Literature

13.7 Chemical-Gene Co-Occurrences in Literature

13.8 Chemical-Disease Co-Occurrences in Literature

14 Patents

14.1 Depositor-Supplied Patent Identifiers

14.2 WIPO PATENTSCOPE

14.3 Chemical Co-Occurrences in Patents

14.4 Chemical-Disease Co-Occurrences in Patents

14.5 Chemical-Gene Co-Occurrences in Patents

15 Interactions and Pathways

15.1 Chemical-Target Interactions

16 Biological Test Results

16.1 BioAssay Results

17 Classification

17.1 ChemIDplus

17.2 CAMEO Chemicals

17.3 UN GHS Classification

17.4 EPA CPDat Classification

17.5 NORMAN Suspect List Exchange Classification

17.6 EPA DSSTox Classification

17.7 Consumer Product Information Database Classification

17.8 EPA TSCA and CDR Classification

17.9 EPA Substance Registry Services Tree

17.10 MolGenie Organic Chemistry Ontology

18 Information Sources

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    CompTox Chemicals Dashboard Chemical Lists
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  16. Toxin and Toxin Target Database (T3DB)
    LICENSE
    T3DB is offered to the public as a freely available resource. Use and re-distribution of the data, in whole or in part, for commercial purposes requires explicit permission of the authors and explicit acknowledgment of the source material (T3DB) and the original publication.
    http://www.t3db.ca/downloads
  17. ChEMBL
    LICENSE
    Access to the web interface of ChEMBL is made under the EBI's Terms of Use (http://www.ebi.ac.uk/Information/termsofuse.html). The ChEMBL data is made available on a Creative Commons Attribution-Share Alike 3.0 Unported License (http://creativecommons.org/licenses/by-sa/3.0/).
    http://www.ebi.ac.uk/Information/termsofuse.html
  18. Consumer Product Information Database (CPID)
    LICENSE
    Copyright (c) 2024 DeLima Associates. All rights reserved. Unless otherwise indicated, all materials from CPID are copyrighted by DeLima Associates. No part of these materials, either text or image may be used for any purpose other than for personal use. Therefore, reproduction, modification, storage in a retrieval system or retransmission, in any form or by any means, electronic, mechanical or otherwise, for reasons other than personal use, is strictly prohibited without prior written permission.
    https://www.whatsinproducts.com/contents/view/1/6
    Consumer Products Category Classification
    https://www.whatsinproducts.com/
  19. Crystallography Open Database (COD)
    LICENSE
    All data in the COD and the database itself are dedicated to the public domain and licensed under the CC0 License. Users of the data should acknowledge the original authors of the structural data.
    https://creativecommons.org/publicdomain/zero/1.0/
  20. EPA Chemical and Products Database (CPDat)
  21. Hazardous Chemical Information System (HCIS), Safe Work Australia
  22. Regulation (EC) No 1272/2008 of the European Parliament and of the Council
    LICENSE
    The copyright for the editorial content of this source, the summaries of EU legislation and the consolidated texts, which is owned by the EU, is licensed under the Creative Commons Attribution 4.0 International licence.
    https://eur-lex.europa.eu/content/legal-notice/legal-notice.html
  23. SpectraBase
    Polymer mixture of poly(i-butylene) and an ester-type compound
    https://spectrabase.com/spectrum/IAfBjWwP4VX
  24. NMRShiftDB
  25. MassBank Europe
  26. Human Metabolome Database (HMDB)
    LICENSE
    HMDB is offered to the public as a freely available resource. Use and re-distribution of the data, in whole or in part, for commercial purposes requires explicit permission of the authors and explicit acknowledgment of the source material (HMDB) and the original publication (see the HMDB citing page). We ask that users who download significant portions of the database cite the HMDB paper in any resulting publications.
    http://www.hmdb.ca/citing
  27. Japan Chemical Substance Dictionary (Nikkaji)
  28. MassBank of North America (MoNA)
    LICENSE
    The content of the MoNA database is licensed under CC BY 4.0.
    https://mona.fiehnlab.ucdavis.edu/documentation/license
  29. NIST Mass Spectrometry Data Center
    LICENSE
    Data covered by the Standard Reference Data Act of 1968 as amended.
    https://www.nist.gov/srd/public-law
  30. Metabolomics Workbench
  31. Nature Chemistry
  32. Springer Nature
  33. SpringerMaterials
  34. Thieme Chemistry
    LICENSE
    The Thieme Chemistry contribution within PubChem is provided under a CC-BY-NC-ND 4.0 license, unless otherwise stated.
    https://creativecommons.org/licenses/by-nc-nd/4.0/
  35. Wikidata
  36. Wikipedia
  37. Wiley
  38. PubChem
  39. GHS Classification (UNECE)
  40. NORMAN Suspect List Exchange
    LICENSE
    Data: CC-BY 4.0; Code (hosted by ECI, LCSB): Artistic-2.0
    https://creativecommons.org/licenses/by/4.0/
    NORMAN Suspect List Exchange Classification
    https://www.norman-network.com/nds/SLE/
  41. EPA Substance Registry Services
  42. MolGenie
    MolGenie Organic Chemistry Ontology
    https://github.com/MolGenie/ontology/
  43. PATENTSCOPE (WIPO)
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