4-Hydroxy-2-pentenal

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  • Identifiers

    CAS number
    16931-17-2

    Molecular formula
    C5H8O2

    SMILES
    CC(C=CC=O)O

    Safety labels

  • Odor profile

    Fragrance
    Green 54.37%
    Pungent 50.18%
    Spicy 35.56%
    Nutty 34.55%
    Earthy 33.69%
    Sharp 33.05%
    Vegetable 31.6%
    Caramellic 30.3%
    Ethereal 30.05%
    Fruity 29.93%

     

    Flavor
    Pungent 41.31%
    Green 29.26%
    Ethereal 26.29%
    Mustard 23.61%
    Fruity 22.79%
    Nutty 21.68%
    Sweet 21.67%
    Formyl 20.99%
    Sharp 20.67%
    Odorless 20.58%

     

    Odor impact est.
    High

  • Properties

    XLogP3-AA
    -0.3

    pKa est.
    7.61 (neutral)

    Molecular weight
    100.12 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Slow

    Boiling point est.
    232°C

    Flash point

    • 83.43 ˚C est.

  • Synonyms

    • 4-hydroxy-2-pentenal
    • 16931-17-2
    • RefChem:1070752
    • 4-hydroxypent-2-enal
    • SCHEMBL3674559
    • SCHEMBL27651481
    • SCHEMBL27999817
    • DTXSID20937622
    • 16931-17-2

  • Applications

    4-Hydroxy-2-pentenal (CAS 16931-17-2) is typically used as a reactive intermediate in organic synthesis, serving as a building block for fragrance and flavor compounds in the perfumery and flavor industries. It can also function as a precursor in polymer and coating formulations, where its aldehyde and hydroxyl groups enable further functionalization or crosslinking. In industrial manufacturing, it may be used as a specialty chemical intermediate for process development and materials synthesis, with usage subject to local regulations.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 324.96
    methanol 622.76
    isopropanol 183.05
    water 109.5
    ethyl acetate 65.75
    n-propanol 196.18
    acetone 139.71
    n-butanol 160.26
    acetonitrile 103.52
    DMF 595.48
    toluene 12.76
    isobutanol 111.67
    1,4-dioxane 154.03
    methyl acetate 91.13
    THF 184.17
    2-butanone 76.48
    n-pentanol 92.75
    sec-butanol 118.23
    n-hexane 4.5
    ethylene glycol 282.04
    NMP 230.01
    cyclohexane 4.68
    DMSO 347.79
    n-butyl acetate 44.96
    n-octanol 43.43
    chloroform 42.92
    n-propyl acetate 38.15
    acetic acid 269.24
    dichloromethane 43.6
    cyclohexanone 85.95
    propylene glycol 215.02
    isopropyl acetate 32.21
    DMAc 328.44
    2-ethoxyethanol 189.63
    isopentanol 95.98
    n-heptane 6.44
    ethyl formate 86.94
    1,2-dichloroethane 35.45
    n-hexanol 93.15
    2-methoxyethanol 413.51
    isobutyl acetate 24.06
    tetrachloromethane 13.77
    n-pentyl acetate 25.53
    transcutol 297.45
    n-heptanol 39.14
    ethylbenzene 9.92
    MIBK 36.38
    2-propoxyethanol 164.72
    tert-butanol 183.56
    MTBE 57.08
    2-butoxyethanol 82.6
    propionic acid 165.13
    o-xylene 16.88
    formic acid 333.48
    diethyl ether 49.77
    m-xylene 15.66
    p-xylene 13.04
    chlorobenzene 19.0
    dimethyl carbonate 38.19
    n-octane 2.64
    formamide 255.53
    cyclopentanone 112.16
    2-pentanone 62.2
    anisole 42.27
    cyclopentyl methyl ether 58.4
    gamma-butyrolactone 135.3
    1-methoxy-2-propanol 204.59
    pyridine 67.29
    3-pentanone 38.89
    furfural 145.99
    n-dodecane 2.84
    diethylene glycol 233.58
    diisopropyl ether 12.83
    tert-amyl alcohol 110.92
    acetylacetone 68.28
    n-hexadecane 2.96
    acetophenone 41.69
    methyl propionate 65.23
    isopentyl acetate 37.1
    trichloroethylene 57.81
    n-nonanol 36.35
    cyclohexanol 76.82
    benzyl alcohol 54.42
    2-ethylhexanol 43.62
    isooctanol 29.37
    dipropyl ether 34.5
    1,2-dichlorobenzene 21.3
    ethyl lactate 45.79
    propylene carbonate 69.0
    n-methylformamide 290.85
    2-pentanol 72.19
    n-pentane 4.9
    1-propoxy-2-propanol 104.29
    1-methoxy-2-propyl acetate 55.19
    2-(2-methoxypropoxy) propanol 92.85
    mesitylene 11.69
    ε-caprolactone 76.42
    p-cymene 13.48
    epichlorohydrin 104.73
    1,1,1-trichloroethane 26.08
    2-aminoethanol 311.89
    morpholine-4-carbaldehyde 249.17
    sulfolane 150.82
    2,2,4-trimethylpentane 4.09
    2-methyltetrahydrofuran 93.35
    n-hexyl acetate 40.66
    isooctane 3.4
    2-(2-butoxyethoxy)ethanol 113.77
    sec-butyl acetate 23.58
    tert-butyl acetate 37.17
    decalin 4.25
    glycerin 282.55
    diglyme 176.04
    acrylic acid 171.43
    isopropyl myristate 19.27
    n-butyric acid 130.96
    acetyl acetate 39.23
    di(2-ethylhexyl) phthalate 26.28
    ethyl propionate 35.89
    nitromethane 267.91
    1,2-diethoxyethane 59.13
    benzonitrile 45.2
    trioctyl phosphate 20.19
    1-bromopropane 19.53
    gamma-valerolactone 167.75
    n-decanol 27.32
    triethyl phosphate 24.69
    4-methyl-2-pentanol 37.7
    propionitrile 79.2
    vinylene carbonate 70.91
    1,1,2-trichlorotrifluoroethane 139.72
    DMS 38.71
    cumene 11.04
    2-octanol 23.5
    2-hexanone 39.61
    octyl acetate 26.31
    limonene 19.81
    1,2-dimethoxyethane 198.76
    ethyl orthosilicate 23.79
    tributyl phosphate 24.16
    diacetone alcohol 83.98
    N,N-dimethylaniline 37.74
    acrylonitrile 109.23
    aniline 46.24
    1,3-propanediol 288.06
    bromobenzene 12.59
    dibromomethane 26.31
    1,1,2,2-tetrachloroethane 49.11
    2-methyl-cyclohexyl acetate 30.94
    tetrabutyl urea 37.01
    diisobutyl methanol 25.62
    2-phenylethanol 49.4
    styrene 12.33
    dioctyl adipate 33.32
    dimethyl sulfate 71.7
    ethyl butyrate 37.71
    methyl lactate 82.38
    butyl lactate 37.53
    diethyl carbonate 28.8
    propanediol butyl ether 96.13
    triethyl orthoformate 31.11
    p-tert-butyltoluene 13.56
    methyl 4-tert-butylbenzoate 45.28
    morpholine 196.14
    tert-butylamine 88.57
    n-dodecanol 21.54
    dimethoxymethane 162.39
    ethylene carbonate 56.79
    cyrene 75.9
    2-ethoxyethyl acetate 41.82
    2-ethylhexyl acetate 27.08
    1,2,4-trichlorobenzene 28.2
    4-methylpyridine 67.02
    dibutyl ether 26.15
    2,6-dimethyl-4-heptanol 25.62
    DEF 120.43
    dimethyl isosorbide 105.44
    tetrachloroethylene 41.7
    eugenol 59.29
    triacetin 48.97
    span 80 71.93
    1,4-butanediol 127.62
    1,1-dichloroethane 28.67
    2-methyl-1-pentanol 68.62
    methyl formate 181.01
    2-methyl-1-butanol 93.06
    n-decane 4.13
    butyronitrile 74.46
    3,7-dimethyl-1-octanol 37.92
    1-chlorooctane 14.48
    1-chlorotetradecane 7.2
    n-nonane 3.89
    undecane 3.31
    tert-butylcyclohexane 4.93
    cyclooctane 2.25
    cyclopentanol 106.12
    tetrahydropyran 84.59
    tert-amyl methyl ether 45.12
    2,5,8-trioxanonane 147.46
    1-hexene 15.29
    2-isopropoxyethanol 99.81
    2,2,2-trifluoroethanol 117.37
    methyl butyrate 53.94

    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