3-Methyl-1-butene

Overview IFRA Request a quote

  • Identifiers

    CAS number
    563-45-1

    Molecular formula
    C5H10

    SMILES
    CC(C)C=C

    Safety labels

    Flammable
    Flammable

    Irritant
    Irritant

    Health Hazard
    Health

  • Odor profile

    Fragrance
    Green 59.32%
    Fruity 57.44%
    Fresh 48.24%
    Gassy 43.47%
    Herbal 40.99%
    Pungent 40.91%
    Ethereal 38.51%
    Woody 28.35%
    Sharp 28.34%
    Earthy 24.13%

     

    Flavor
    Citrus 27.54%
    Green 25.86%
    Pungent 21.18%
    Fishy 20.88%
    Glue 20.69%
    Solvent 19.77%
    Yeasty 19.36%
    Bloody 19.27%
    Fresh 19.24%
    Terpentine 19.23%

     

    Odor impact est.
    Low

  • Properties

    XLogP3-AA
    2.2

    pKa est.
    9.3 (weak base)

    Molecular weight
    70.13 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Ultra fast

    Melting point expt.

    • -168.5 °C

    Boiling point

    • 20.1 °C

    Flash point

    • -53.21 ˚C est.
    • less than 20 °F (NFPA, 2010)
    • -57 °C
    • BELOW 20 °F (BELOW -7 °C) (CLOSED CUP)

    Solubility expt.

    • Soluble in benzene; miscible in ethanol and ethyl ether
    • In water, 130 mg/l @ 25 °C.

  • Synonyms

    • 3-METHYL-1-BUTENE
    • 563-45-1
    • 3-Methylbut-1-ene
    • Isopentene
    • Isopropylethylene
    • 1-Butene, 3-methyl-
    • 2-Methyl-3-butene
    • Vinylisopropyl
    • Isopropylethene
    • alpha-Isoamylene
    • Isoamylene
    • UNII-I08ZWX8BKL
    • I08ZWX8BKL
    • .alpha.-Isoamylene
    • 3-Methylbutene-1
    • 3,3-dimethylpropene
    • HSDB 5696
    • EINECS 209-249-1
    • UN2561
    • (CH3)2CHCH=CH2
    • DTXSID7060336
    • CHEBI:77914
    • 3-METHYL-1-BUTENE [HSDB]
    • MFCD00008937
    • UN 2561
    • 3-Methyl-1-butene (ca. 15% in Dichloromethane, ca. 2.5mol/L)
    • 3-Methyl-1-butene (ca. 12.5% in Tetrahydrofuran, ca. 1.5mol/L)
    • alphaIsoamylene
    • 2Methyl3butene
    • 3Methylbut1ene
    • 1Butene, 3methyl
    • 3-methyl-1-butylene
    • 3-methylbut-1-en-4-yl
    • 3-Methyl-1-butene [UN2561] [Flammable liquid]
    • 3-Methyl-1-butene, 95%
    • DTXCID4042048
    • DTXSID30967359
    • AKOS009159414
    • 3-Methyl-1-butene, analytical standard
    • DB-000196
    • M0177
    • M2563
    • M2564
    • M2565
    • NS00020842
    • 3-Methyl-1-butene 100 microg/mL in Methanol
    • Q27147525
    • 3-Methyl-1-butene (ca. 16.5% in N,N-Dimethylformamide, ca. 2mol/L)

  • Applications

    3-Methyl-1-butene (CAS 563-45-1) is primarily used as a C5 alpha-olefin feedstock and intermediate in industrial synthesis. In polymers and plastics, it serves as a comonomer to tailor the properties of polyolefins. In fragrance and flavor chemistry, it acts as a precursor for downstream transformations to isoamyl alcohol (3-methyl-1-butanol) and related isoamyl esters used in flavor and fragrance formulations. It also provides a pathway via hydroformylation and hydrogenation to access higher aldehydes and alcohols for various specialty chemicals. Its use is subject to local regulations and formulation limits.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 89.77
    methanol 57.33
    isopropanol 89.36
    water 0.12
    ethyl acetate 147.11
    n-propanol 105.4
    acetone 67.16
    n-butanol 142.71
    acetonitrile 63.24
    DMF 54.2
    toluene 84.57
    isobutanol 78.08
    1,4-dioxane 159.65
    methyl acetate 94.85
    THF 287.32
    2-butanone 117.88
    n-pentanol 96.74
    sec-butanol 129.41
    n-hexane 165.92
    ethylene glycol 12.45
    NMP 87.52
    cyclohexane 119.09
    DMSO 57.49
    n-butyl acetate 291.29
    n-octanol 110.83
    chloroform 277.18
    n-propyl acetate 93.96
    acetic acid 51.08
    dichloromethane 167.84
    cyclohexanone 138.93
    propylene glycol 33.19
    isopropyl acetate 110.5
    DMAc 80.52
    2-ethoxyethanol 75.07
    isopentanol 122.42
    n-heptane 269.17
    ethyl formate 44.98
    1,2-dichloroethane 103.9
    n-hexanol 259.52
    2-methoxyethanol 94.8
    isobutyl acetate 72.66
    tetrachloromethane 88.74
    n-pentyl acetate 110.9
    transcutol 349.66
    n-heptanol 115.35
    ethylbenzene 60.78
    MIBK 86.15
    2-propoxyethanol 211.79
    tert-butanol 136.57
    MTBE 187.97
    2-butoxyethanol 120.06
    propionic acid 67.55
    o-xylene 62.75
    formic acid 10.1
    diethyl ether 207.05
    m-xylene 66.84
    p-xylene 64.67
    chlorobenzene 88.86
    dimethyl carbonate 24.74
    n-octane 69.77
    formamide 13.27
    cyclopentanone 151.16
    2-pentanone 120.59
    anisole 84.83
    cyclopentyl methyl ether 171.33
    gamma-butyrolactone 113.0
    1-methoxy-2-propanol 110.4
    pyridine 131.88
    3-pentanone 105.29
    furfural 98.54
    n-dodecane 38.2
    diethylene glycol 84.55
    diisopropyl ether 103.9
    tert-amyl alcohol 171.51
    acetylacetone 90.08
    n-hexadecane 40.39
    acetophenone 67.88
    methyl propionate 83.62
    isopentyl acetate 198.07
    trichloroethylene 170.73
    n-nonanol 107.55
    cyclohexanol 118.14
    benzyl alcohol 53.17
    2-ethylhexanol 226.87
    isooctanol 92.91
    dipropyl ether 343.91
    1,2-dichlorobenzene 78.85
    ethyl lactate 42.43
    propylene carbonate 90.92
    n-methylformamide 27.43
    2-pentanol 132.58
    n-pentane 124.2
    1-propoxy-2-propanol 252.05
    1-methoxy-2-propyl acetate 167.67
    2-(2-methoxypropoxy) propanol 137.12
    mesitylene 49.87
    ε-caprolactone 136.28
    p-cymene 90.99
    epichlorohydrin 131.31
    1,1,1-trichloroethane 172.43
    2-aminoethanol 33.43
    morpholine-4-carbaldehyde 95.3
    sulfolane 114.75
    2,2,4-trimethylpentane 59.33
    2-methyltetrahydrofuran 264.12
    n-hexyl acetate 145.24
    isooctane 44.46
    2-(2-butoxyethoxy)ethanol 175.48
    sec-butyl acetate 88.38
    tert-butyl acetate 127.62
    decalin 61.55
    glycerin 34.33
    diglyme 226.89
    acrylic acid 45.73
    isopropyl myristate 86.08
    n-butyric acid 123.48
    acetyl acetate 80.19
    di(2-ethylhexyl) phthalate 62.5
    ethyl propionate 95.56
    nitromethane 52.57
    1,2-diethoxyethane 227.5
    benzonitrile 72.11
    trioctyl phosphate 51.82
    1-bromopropane 176.27
    gamma-valerolactone 129.69
    n-decanol 86.52
    triethyl phosphate 78.2
    4-methyl-2-pentanol 88.06
    propionitrile 97.06
    vinylene carbonate 62.3
    1,1,2-trichlorotrifluoroethane 95.1
    DMS 67.42
    cumene 50.74
    2-octanol 83.59
    2-hexanone 111.82
    octyl acetate 101.36
    limonene 153.24
    1,2-dimethoxyethane 132.65
    ethyl orthosilicate 88.24
    tributyl phosphate 63.51
    diacetone alcohol 114.63
    N,N-dimethylaniline 64.77
    acrylonitrile 69.72
    aniline 79.85
    1,3-propanediol 54.28
    bromobenzene 99.14
    dibromomethane 174.61
    1,1,2,2-tetrachloroethane 173.44
    2-methyl-cyclohexyl acetate 126.23
    tetrabutyl urea 71.73
    diisobutyl methanol 134.21
    2-phenylethanol 103.77
    styrene 67.78
    dioctyl adipate 94.24
    dimethyl sulfate 30.17
    ethyl butyrate 202.16
    methyl lactate 38.81
    butyl lactate 79.36
    diethyl carbonate 109.77
    propanediol butyl ether 84.34
    triethyl orthoformate 157.0
    p-tert-butyltoluene 92.47
    methyl 4-tert-butylbenzoate 94.67
    morpholine 178.89
    tert-butylamine 130.99
    n-dodecanol 73.74
    dimethoxymethane 61.52
    ethylene carbonate 57.02
    cyrene 65.04
    2-ethoxyethyl acetate 110.65
    2-ethylhexyl acetate 187.96
    1,2,4-trichlorobenzene 92.42
    4-methylpyridine 112.04
    dibutyl ether 215.65
    2,6-dimethyl-4-heptanol 134.21
    DEF 107.55
    dimethyl isosorbide 171.31
    tetrachloroethylene 114.54
    eugenol 83.09
    triacetin 104.14
    span 80 151.35
    1,4-butanediol 22.38
    1,1-dichloroethane 137.53
    2-methyl-1-pentanol 105.9
    methyl formate 17.73
    2-methyl-1-butanol 121.17
    n-decane 63.91
    butyronitrile 118.8
    3,7-dimethyl-1-octanol 130.32
    1-chlorooctane 111.52
    1-chlorotetradecane 55.04
    n-nonane 72.17
    undecane 47.12
    tert-butylcyclohexane 64.42
    cyclooctane 69.24
    cyclopentanol 97.31
    tetrahydropyran 248.52
    tert-amyl methyl ether 174.31
    2,5,8-trioxanonane 172.26
    1-hexene 222.59
    2-isopropoxyethanol 79.73
    2,2,2-trifluoroethanol 16.92
    methyl butyrate 102.85

    Scent© AI

1 4

IFRA standard 51

Recommendation
No restriction
Maximum acceptable concentrations in the finished product (%)
Category 1
Products applied to the lips
 No restriction Category 7A
Rinse-off products applied to the hair with some hand contact
 No restriction
Category 2
Products applied to the axillae
 No restriction Category 7B
Leave-on products applied to the hair with some hand contact
 No restriction
Category 3
Products applied to the face/body using fingertips
 No restriction Category 8
Products with significant anogenital exposure
 No restriction
Category 4
Products related to fine fragrance
 No restriction Category 9
Products with body and hand exposure, primarily rinse off
 No restriction
Category 5A
Body lotion products applied to the body using the hands (palms), primarily leave on
 No restriction Category 10A
Household care products with mostly hand contact
 No restriction
Category 5B
Face moisturizer products applied to the face using the hands (palms), primarily leave on
 No restriction Category 10B
Household care products with mostly hand contact, including aerosol/spray products (with potential leave-on skin contact)
 No restriction
Category 5C
Hand cream products applied to the hands using the hands (palms), primarily leave on
 No restriction Category 11A
Products with intended skin contact but minimal transfer of fragrance to skin from inert substrate without UV exposure
 No restriction
Category 5D
Baby Creams, baby Oils and baby talc
 No restriction Category 11B
Products with intended skin contact but minimal transfer of fragrance to skin from inert substrate with potential UV exposure
 No restriction
Category 6
Products with oral and lip exposure
 No restriction Category 12
Products not intended for direct skin contact, minimal or insignificant transfer to skin
 No restriction