2-Isobutyl-3,5-dimethyl-pyrazine

Overview IFRA Request a quote

  • Identifiers

    CAS number
    70303-42-3

    Molecular formula
    C10H16N2

    SMILES
    CC1=CN=C(C(=N1)C)CC(C)C

  • Odor profile

    Fragrance
    Earthy 47.79%
    Nutty 46.28%
    Burnt 41.89%
    Roasted 40.47%
    Green 39.54%
    Woody 37.73%
    Cocoa 36.87%
    Fruity 36.38%
    Musty 35.35%
    Mint 34.01%

     

    Flavor
    Earthy 49.91%
    Musty 45.02%
    Roasted 42.19%
    Earth 39.24%
    Burnt 38.12%
    Cocoa 37.29%
    Hazelnut 34.67%
    Green 32.58%
    Nutty 32.22%
    Pepper 31.17%

     

    Odor impact est.
    High

  • Properties

    XLogP3-AA
    2.2

    pKa est.
    5.25 (weak acid)

    Molecular weight
    164.25 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Moderately slow

    Boiling point est.
    238°C

    Flash point

    • 91.97 ˚C est.

  • Synonyms

    • 3,5-Dimethyl-2-isobutylpyrazine
    • 70303-42-3
    • 3,5-dimethyl-2-(2-methylpropyl)pyrazine
    • 2-Isobutyl-3,5-dimethylpyrazine
    • 2-Isobutyl-3,5-dimethyl-pyrazine
    • UNII-3XH091289A
    • Pyrazine, 3,5-dimethyl-2-(2-methylpropyl)-
    • 3XH091289A
    • FEMA No. 4100, 3,5-dimethyl-
    • 2-(2-Methylpropyl)-3,5-dimethylpyrazine
    • 2,6-Dimethyl-5-isobutylpyrazine
    • DTXSID80220582
    • 2,6-Dimethyl-3-(2-methylpropyl)pyrazine
    • 3,5- AND 3,6-DIMETHYL-2-ISOBUTYLPYRAZINE
    • SCHEMBL3458106
    • DTXCID10143073
    • 2-Isobutyl-3,5-dimethylpyrazine #
    • AKOS006272104
    • DB-117080
    • NS00113907
    • Q27258180

  • Applications

    2-Isobutyl-3,5-dimethyl-pyrazine (CAS 70303-42-3) is commonly used as an odorant in perfumery and as a flavor component in savory food applications, contributing roasted, nutty, and meat-like notes. It is also used in cosmetics and personal care formulations as a fragrance ingredient, and in household products such as air fresheners and cleaners to impart a distinctive aroma. In industrial manufacturing, it may serve as an intermediate for the synthesis of related pyrazine derivatives, and it can be found in coatings or inks where fragrance notes are desired. Its use is typically subject to local regulations and formulation limits.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 256.66
    methanol 303.98
    isopropanol 241.84
    water 1.81
    ethyl acetate 284.96
    n-propanol 299.34
    acetone 338.63
    n-butanol 346.71
    acetonitrile 168.71
    DMF 457.99
    toluene 327.14
    isobutanol 324.2
    1,4-dioxane 530.47
    methyl acetate 293.88
    THF 834.55
    2-butanone 362.51
    n-pentanol 276.81
    sec-butanol 312.06
    n-hexane 217.26
    ethylene glycol 76.51
    NMP 594.04
    cyclohexane 232.91
    DMSO 298.27
    n-butyl acetate 419.32
    n-octanol 217.42
    chloroform 1237.82
    n-propyl acetate 202.28
    acetic acid 321.15
    dichloromethane 800.42
    cyclohexanone 688.06
    propylene glycol 131.1
    isopropyl acetate 223.25
    DMAc 536.91
    2-ethoxyethanol 227.54
    isopentanol 364.17
    n-heptane 100.97
    ethyl formate 227.49
    1,2-dichloroethane 510.59
    n-hexanol 507.53
    2-methoxyethanol 357.81
    isobutyl acetate 197.87
    tetrachloromethane 290.89
    n-pentyl acetate 242.84
    transcutol 523.85
    n-heptanol 214.6
    ethylbenzene 191.34
    MIBK 241.09
    2-propoxyethanol 486.24
    tert-butanol 321.77
    MTBE 451.64
    2-butoxyethanol 269.91
    propionic acid 280.44
    o-xylene 229.12
    formic acid 99.91
    diethyl ether 366.72
    m-xylene 241.25
    p-xylene 269.77
    chlorobenzene 423.62
    dimethyl carbonate 140.2
    n-octane 49.22
    formamide 77.14
    cyclopentanone 660.61
    2-pentanone 299.88
    anisole 226.21
    cyclopentyl methyl ether 522.67
    gamma-butyrolactone 625.51
    1-methoxy-2-propanol 296.9
    pyridine 443.81
    3-pentanone 311.08
    furfural 556.82
    n-dodecane 35.79
    diethylene glycol 285.25
    diisopropyl ether 168.98
    tert-amyl alcohol 362.04
    acetylacetone 290.09
    n-hexadecane 40.52
    acetophenone 223.71
    methyl propionate 258.48
    isopentyl acetate 404.37
    trichloroethylene 988.41
    n-nonanol 182.62
    cyclohexanol 437.14
    benzyl alcohol 211.64
    2-ethylhexanol 316.46
    isooctanol 178.21
    dipropyl ether 257.73
    1,2-dichlorobenzene 371.87
    ethyl lactate 127.28
    propylene carbonate 448.45
    n-methylformamide 181.23
    2-pentanol 269.15
    n-pentane 137.19
    1-propoxy-2-propanol 354.25
    1-methoxy-2-propyl acetate 303.72
    2-(2-methoxypropoxy) propanol 210.56
    mesitylene 165.77
    ε-caprolactone 560.65
    p-cymene 148.67
    epichlorohydrin 618.83
    1,1,1-trichloroethane 645.44
    2-aminoethanol 146.41
    morpholine-4-carbaldehyde 488.94
    sulfolane 660.13
    2,2,4-trimethylpentane 97.19
    2-methyltetrahydrofuran 682.93
    n-hexyl acetate 358.5
    isooctane 58.8
    2-(2-butoxyethoxy)ethanol 262.52
    sec-butyl acetate 178.27
    tert-butyl acetate 262.78
    decalin 112.87
    glycerin 164.29
    diglyme 422.2
    acrylic acid 247.08
    isopropyl myristate 135.7
    n-butyric acid 417.17
    acetyl acetate 223.2
    di(2-ethylhexyl) phthalate 144.36
    ethyl propionate 179.56
    nitromethane 292.25
    1,2-diethoxyethane 279.46
    benzonitrile 295.44
    trioctyl phosphate 109.94
    1-bromopropane 426.92
    gamma-valerolactone 662.16
    n-decanol 136.12
    triethyl phosphate 126.24
    4-methyl-2-pentanol 181.61
    propionitrile 228.34
    vinylene carbonate 383.31
    1,1,2-trichlorotrifluoroethane 490.2
    DMS 241.35
    cumene 147.82
    2-octanol 162.66
    2-hexanone 259.48
    octyl acetate 176.15
    limonene 223.79
    1,2-dimethoxyethane 387.65
    ethyl orthosilicate 135.54
    tributyl phosphate 139.3
    diacetone alcohol 256.71
    N,N-dimethylaniline 191.67
    acrylonitrile 231.85
    aniline 281.69
    1,3-propanediol 224.0
    bromobenzene 468.95
    dibromomethane 625.88
    1,1,2,2-tetrachloroethane 946.24
    2-methyl-cyclohexyl acetate 237.37
    tetrabutyl urea 163.41
    diisobutyl methanol 156.18
    2-phenylethanol 287.87
    styrene 206.91
    dioctyl adipate 159.49
    dimethyl sulfate 217.14
    ethyl butyrate 210.43
    methyl lactate 149.93
    butyl lactate 197.59
    diethyl carbonate 150.75
    propanediol butyl ether 232.92
    triethyl orthoformate 179.83
    p-tert-butyltoluene 146.29
    methyl 4-tert-butylbenzoate 211.6
    morpholine 514.59
    tert-butylamine 254.61
    n-dodecanol 106.83
    dimethoxymethane 284.47
    ethylene carbonate 338.21
    cyrene 220.01
    2-ethoxyethyl acetate 250.84
    2-ethylhexyl acetate 351.16
    1,2,4-trichlorobenzene 445.89
    4-methylpyridine 507.59
    dibutyl ether 243.63
    2,6-dimethyl-4-heptanol 156.18
    DEF 354.39
    dimethyl isosorbide 345.15
    tetrachloroethylene 664.82
    eugenol 212.72
    triacetin 225.54
    span 80 215.76
    1,4-butanediol 122.38
    1,1-dichloroethane 564.46
    2-methyl-1-pentanol 313.37
    methyl formate 188.89
    2-methyl-1-butanol 389.03
    n-decane 61.3
    butyronitrile 283.51
    3,7-dimethyl-1-octanol 210.4
    1-chlorooctane 197.63
    1-chlorotetradecane 77.8
    n-nonane 68.13
    undecane 44.54
    tert-butylcyclohexane 109.91
    cyclooctane 93.06
    cyclopentanol 390.41
    tetrahydropyran 662.31
    tert-amyl methyl ether 387.05
    2,5,8-trioxanonane 267.89
    1-hexene 349.74
    2-isopropoxyethanol 192.82
    2,2,2-trifluoroethanol 150.07
    methyl butyrate 254.5

    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