4-Ethyl-1,3-oxazole

Overview IFRA Request a quote

  • Identifiers

    CAS number
    54300-20-8

    Molecular formula
    C5H7NO

    SMILES
    CCC1=COC=N1

    Safety labels

    Flammable
    Flammable

    Irritant
    Irritant

  • Odor profile

    Fragrance
    Green 79.53%
    Nutty 64.06%
    Roasted 53.98%
    Vegetable 53.87%
    Earthy 45.96%
    Musty 42.26%
    Meaty 42.21%
    Cocoa 40.97%
    Burnt 40.28%
    Coffee 35.95%

     

    Flavor
    Nutty 67.47%
    Green 60.53%
    Earthy 43.4%
    Sweet 40.83%
    Vegetable 40.56%
    Roasted 40.08%
    Coffee 34.22%
    Caramel 33.8%
    Musty 32.95%
    Potato 31.61%

     

    Odor impact est.
    High

  • Properties

    XLogP3-AA
    1.2

    pKa est.
    5.71 (weak acid)

    Molecular weight
    97.12 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Ultra fast

    Boiling point est.
    103°C

    Flash point

    • 33.28 ˚C est.

  • Synonyms

    • 4-ethyl-1,3-oxazole
    • RefChem:522710
    • 832-576-1
    • 54300-20-8
    • Oxazole, 4-ethyl-
    • 4-ethyloxazole
    • 4-ethyl-oxazole
    • MFCD16249872
    • SCHEMBL357742
    • SCHEMBL357743
    • SCHEMBL684672
    • SCHEMBL1818034
    • SCHEMBL2040998
    • DA-20383
    • C77618
    • EN300-306624
    • 54300-20-8

  • Applications

    4-Ethyl-1,3-oxazole (CAS 54300-20-8) serves as a versatile building block in organic synthesis, commonly used as an intermediate in pharmaceutical and agrochemical development to construct heterocyclic oxazole-containing drug and agrochemical candidates. In industrial manufacturing, it is employed as a precursor for oxazole motifs and related structures in medicinal chemistry research. It also finds use in polymers and specialty materials, where it can be incorporated as a functional precursor for oxazole-containing polymers or crosslinking additives. In coatings and inks, it is used as an intermediate to access advanced formulations and performance additives. In academic and process development settings, it may be used as a reagent or starting material for the synthesis of novel heterocyclic compounds and libraries.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 624.13
    methanol 1188.28
    isopropanol 334.05
    water 20.34
    ethyl acetate 243.0
    n-propanol 388.84
    acetone 387.84
    n-butanol 351.16
    acetonitrile 423.74
    DMF 549.53
    toluene 121.39
    isobutanol 291.51
    1,4-dioxane 421.03
    methyl acetate 251.91
    THF 614.83
    2-butanone 274.81
    n-pentanol 271.49
    sec-butanol 271.16
    n-hexane 37.17
    ethylene glycol 153.65
    NMP 532.23
    cyclohexane 47.39
    DMSO 681.54
    n-butyl acetate 222.7
    n-octanol 103.57
    chloroform 941.19
    n-propyl acetate 149.62
    acetic acid 853.13
    dichloromethane 1075.74
    cyclohexanone 397.85
    propylene glycol 114.14
    isopropyl acetate 123.65
    DMAc 296.61
    2-ethoxyethanol 316.14
    isopentanol 271.55
    n-heptane 30.43
    ethyl formate 244.64
    1,2-dichloroethane 478.85
    n-hexanol 201.27
    2-methoxyethanol 500.64
    isobutyl acetate 102.77
    tetrachloromethane 180.15
    n-pentyl acetate 142.87
    transcutol 807.84
    n-heptanol 102.47
    ethylbenzene 61.88
    MIBK 149.86
    2-propoxyethanol 307.0
    tert-butanol 314.59
    MTBE 215.04
    2-butoxyethanol 181.2
    propionic acid 337.36
    o-xylene 87.69
    formic acid 536.43
    diethyl ether 248.68
    m-xylene 85.29
    p-xylene 99.82
    chlorobenzene 283.28
    dimethyl carbonate 89.41
    n-octane 13.11
    formamide 492.27
    cyclopentanone 481.81
    2-pentanone 235.53
    anisole 156.43
    cyclopentyl methyl ether 251.98
    gamma-butyrolactone 595.16
    1-methoxy-2-propanol 270.33
    pyridine 431.37
    3-pentanone 157.81
    furfural 575.11
    n-dodecane 12.21
    diethylene glycol 256.48
    diisopropyl ether 67.44
    tert-amyl alcohol 264.32
    acetylacetone 225.45
    n-hexadecane 13.47
    acetophenone 149.87
    methyl propionate 181.99
    isopentyl acetate 186.12
    trichloroethylene 899.37
    n-nonanol 88.81
    cyclohexanol 225.01
    benzyl alcohol 161.09
    2-ethylhexanol 114.46
    isooctanol 91.23
    dipropyl ether 119.69
    1,2-dichlorobenzene 242.17
    ethyl lactate 80.83
    propylene carbonate 279.72
    n-methylformamide 403.1
    2-pentanol 197.51
    n-pentane 44.2
    1-propoxy-2-propanol 196.14
    1-methoxy-2-propyl acetate 160.7
    2-(2-methoxypropoxy) propanol 170.66
    mesitylene 63.12
    ε-caprolactone 313.83
    p-cymene 58.28
    epichlorohydrin 574.43
    1,1,1-trichloroethane 414.42
    2-aminoethanol 256.04
    morpholine-4-carbaldehyde 424.31
    sulfolane 652.76
    2,2,4-trimethylpentane 29.21
    2-methyltetrahydrofuran 451.0
    n-hexyl acetate 179.38
    isooctane 21.24
    2-(2-butoxyethoxy)ethanol 238.71
    sec-butyl acetate 89.22
    tert-butyl acetate 141.95
    decalin 25.5
    glycerin 164.88
    diglyme 391.08
    acrylic acid 357.5
    isopropyl myristate 72.67
    n-butyric acid 396.17
    acetyl acetate 153.03
    di(2-ethylhexyl) phthalate 87.71
    ethyl propionate 116.4
    nitromethane 768.59
    1,2-diethoxyethane 260.18
    benzonitrile 275.79
    trioctyl phosphate 60.12
    1-bromopropane 301.4
    gamma-valerolactone 540.06
    n-decanol 65.83
    triethyl phosphate 72.92
    4-methyl-2-pentanol 110.37
    propionitrile 312.56
    vinylene carbonate 281.16
    1,1,2-trichlorotrifluoroethane 364.69
    DMS 135.35
    cumene 54.11
    2-octanol 76.76
    2-hexanone 172.37
    octyl acetate 89.26
    limonene 85.53
    1,2-dimethoxyethane 362.65
    ethyl orthosilicate 70.98
    tributyl phosphate 80.32
    diacetone alcohol 170.68
    N,N-dimethylaniline 112.59
    acrylonitrile 387.76
    aniline 216.08
    1,3-propanediol 317.78
    bromobenzene 289.56
    dibromomethane 632.5
    1,1,2,2-tetrachloroethane 533.34
    2-methyl-cyclohexyl acetate 115.98
    tetrabutyl urea 99.17
    diisobutyl methanol 73.4
    2-phenylethanol 147.13
    styrene 90.3
    dioctyl adipate 102.53
    dimethyl sulfate 151.04
    ethyl butyrate 139.62
    methyl lactate 104.34
    butyl lactate 105.84
    diethyl carbonate 96.48
    propanediol butyl ether 160.86
    triethyl orthoformate 97.64
    p-tert-butyltoluene 54.11
    methyl 4-tert-butylbenzoate 139.53
    morpholine 474.47
    tert-butylamine 225.88
    n-dodecanol 51.13
    dimethoxymethane 289.25
    ethylene carbonate 219.29
    cyrene 166.03
    2-ethoxyethyl acetate 184.97
    2-ethylhexyl acetate 140.22
    1,2,4-trichlorobenzene 264.64
    4-methylpyridine 367.44
    dibutyl ether 117.83
    2,6-dimethyl-4-heptanol 73.4
    DEF 243.73
    dimethyl isosorbide 271.65
    tetrachloroethylene 427.91
    eugenol 159.0
    triacetin 151.9
    span 80 151.41
    1,4-butanediol 154.47
    1,1-dichloroethane 479.96
    2-methyl-1-pentanol 213.59
    methyl formate 304.35
    2-methyl-1-butanol 264.8
    n-decane 18.17
    butyronitrile 335.58
    3,7-dimethyl-1-octanol 108.82
    1-chlorooctane 70.55
    1-chlorotetradecane 31.28
    n-nonane 17.97
    undecane 14.5
    tert-butylcyclohexane 27.13
    cyclooctane 16.54
    cyclopentanol 298.72
    tetrahydropyran 376.21
    tert-amyl methyl ether 152.88
    2,5,8-trioxanonane 286.47
    1-hexene 120.55
    2-isopropoxyethanol 191.79
    2,2,2-trifluoroethanol 251.16
    methyl butyrate 175.14

    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