4-Methylpyrazole

Overview IFRA Request a quote

  • Identifiers

    CAS number
    7554-65-6

    Molecular formula
    C4H6N2

    SMILES
    CC1=CNN=C1

    Safety labels

    Corrosive
    Corrosive

    Irritant
    Irritant

  • Odor profile

    Fragrance
    Nutty 80.43%
    Roasted 77.77%
    Hazelnut 57.39%
    Coffee 55.67%
    Musty 54.0%
    Cocoa 53.9%
    Earthy 52.81%
    Burnt 48.33%
    Potato 47.53%
    Chocolate 42.75%

     

    Flavor
    Nutty 63.72%
    Cocoa 51.37%
    Roasted 49.01%
    Coffee 47.55%
    Musty 42.03%
    Peanut 41.2%
    Woody 40.99%
    Hazelnut 37.87%
    Earthy 36.29%
    Potato 36.1%

     

    Odor impact est.
    High

  • Properties

    XLogP3-AA
    1.4

    pKa est.
    5.84 (weak acid)

    Molecular weight
    82.1 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Moderate

    Boiling point est.
    216°C

    Melting point expt.

    • 25 °C

    Flash point

    • 91.02 ˚C est.

    Solubility expt.

    • 5.59e+02 g/L

  • Synonyms

    • 4-Methylpyrazole
    • fomepizole
    • 7554-65-6
    • 1H-Pyrazole, 4-methyl-
    • 4-Methylpyrazol
    • Fomepizol
    • Fomepizolum
    • 83LCM6L2BY
    • NSC-760365
    • CHEBI:5141
    • DTXSID3040649
    • 4 Methylpyrazole
    • 4 Methylpyrazole Monohydrochloride
    • RefChem:58530
    • DTXCID1020649
    • V03AB34
    • 231-445-0
    • 4-Methyl-1H-pyrazole
    • Antizol
    • Fomepizol [INN-Spanish]
    • Fomepizolum [INN-Latin]
    • 4-MP
    • MFCD00005245
    • Antizol-vet
    • PYRAZOLE, 4-METHYL-
    • 4-methyl pyrazole
    • Fomepizole [USAN:INN]
    • Antizol (TN)
    • EINECS 231-445-0
    • UNII-83LCM6L2BY
    • BRN 0105204
    • Fomepizole [USAN:INN:BAN]
    • 4-methyl-pyrazole
    • Fomepizole, 99%
    • Fomepizole (Antizol)
    • Fomepizole (Standard)
    • 4-methyl-1h_pyrazole
    • FOMEPIZOLE [MI]
    • FOMEPIZOLE [INN]
    • FOMEPIZOLE [JAN]
    • FOMEPIZOLE [USAN]
    • Lopac-M-1387
    • M0774
    • FOMEPIZOLE [VANDF]
    • EC 231-445-0
    • FOMEPIZOLE [MART.]
    • CHEMBL1308
    • FOMEPIZOLE [WHO-DD]
    • Lopac0_000723
    • SCHEMBL10591
    • SCHEMBL75206
    • 5-23-05-00031 (Beilstein Handbook Reference)
    • 615557-09-0
    • MLS001335923
    • Fomepizole (JAN/USAN/INN)
    • SCHEMBL129484
    • SCHEMBL196325
    • SCHEMBL324901
    • orb1310313
    • SCHEMBL1426623
    • SCHEMBL5928979
    • SCHEMBL9905638
    • FOMEPIZOLE [GREEN BOOK]
    • FOMEPIZOLE [ORANGE BOOK]
    • GTPL11705
    • HY-B0876R
    • HMS3713H14
    • HMS3868M13
    • HMS5079N16
    • Pharmakon1600-01506159
    • ALBB-016317
    • HY-B0876
    • BDBM50226186
    • CL3422
    • EBC-03035
    • NSC760365
    • s1717
    • SBB004402
    • STK256626
    • AKOS000265586
    • AB00390
    • AC-4833
    • CCG-204808
    • DB01213
    • FM36058
    • NSC 760365
    • SDCCGSBI-0050701.P003
    • NCGC00015646-01
    • NCGC00015646-02
    • NCGC00015646-03
    • NCGC00015646-04
    • NCGC00015646-10
    • NCGC00162231-01
    • SMR000059088
    • SY006499
    • SBI-0050701.P002
    • DB-022514
    • DB-094915
    • A9615
    • NS00005850
    • ST45123338
    • EN300-50246
    • C07837
    • D00707
    • AB00918526_06
    • AB00918526_07
    • 554M656
    • F043307
    • Q416410
    • BRD-K56810756-001-03-0
    • BRD-K56810756-003-07-7
    • Z600419582
    • 4PZ
    • 7554-65-6

  • Applications

    4-Methylpyrazole is mainly used as an intermediate in the synthesis of pyrazole-containing compounds and as a building block for heterocyclic derivatives in pharmaceutical and agrochemical R&D. It may serve as a precursor for functionalized derivatives used to access more complex pyrazole-containing structures. In organic synthesis, it can act as a solvent or co-solvent in certain reactions. As a functional starting material, it is considered for use in materials research as the starting unit for functionalized pyrazole motifs in polymers, coatings, and inks.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 148.41
    methanol 262.64
    isopropanol 82.86
    water 164.0
    ethyl acetate 36.26
    n-propanol 101.44
    acetone 76.45
    n-butanol 88.48
    acetonitrile 65.82
    DMF 221.48
    toluene 10.8
    isobutanol 79.39
    1,4-dioxane 51.0
    methyl acetate 53.26
    THF 84.29
    2-butanone 59.65
    n-pentanol 65.16
    sec-butanol 72.89
    n-hexane 2.5
    ethylene glycol 94.22
    NMP 138.5
    cyclohexane 1.7
    DMSO 97.93
    n-butyl acetate 27.62
    n-octanol 23.76
    chloroform 87.6
    n-propyl acetate 23.34
    acetic acid 217.83
    dichloromethane 64.3
    cyclohexanone 51.49
    propylene glycol 102.34
    isopropyl acetate 21.39
    DMAc 207.1
    2-ethoxyethanol 110.26
    isopentanol 75.28
    n-heptane 3.36
    ethyl formate 49.32
    1,2-dichloroethane 27.86
    n-hexanol 52.51
    2-methoxyethanol 177.31
    isobutyl acetate 18.59
    tetrachloromethane 21.61
    n-pentyl acetate 24.76
    transcutol 186.89
    n-heptanol 35.61
    ethylbenzene 6.09
    MIBK 28.36
    2-propoxyethanol 97.26
    tert-butanol 78.03
    MTBE 33.34
    2-butoxyethanol 74.08
    propionic acid 104.48
    o-xylene 10.95
    formic acid 235.3
    diethyl ether 25.12
    m-xylene 10.64
    p-xylene 10.78
    chlorobenzene 20.38
    dimethyl carbonate 31.03
    n-octane 1.5
    formamide 215.86
    cyclopentanone 77.82
    2-pentanone 40.98
    anisole 26.7
    cyclopentyl methyl ether 33.65
    gamma-butyrolactone 88.21
    1-methoxy-2-propanol 119.49
    pyridine 51.7
    3-pentanone 30.8
    furfural 107.38
    n-dodecane 1.19
    diethylene glycol 95.25
    diisopropyl ether 7.4
    tert-amyl alcohol 73.49
    acetylacetone 38.24
    n-hexadecane 1.21
    acetophenone 31.4
    methyl propionate 43.63
    isopentyl acetate 26.74
    trichloroethylene 75.38
    n-nonanol 21.38
    cyclohexanol 37.05
    benzyl alcohol 43.38
    2-ethylhexanol 28.29
    isooctanol 28.13
    dipropyl ether 17.21
    1,2-dichlorobenzene 21.28
    ethyl lactate 27.7
    propylene carbonate 54.87
    n-methylformamide 151.94
    2-pentanol 47.1
    n-pentane 3.27
    1-propoxy-2-propanol 67.65
    1-methoxy-2-propyl acetate 34.81
    2-(2-methoxypropoxy) propanol 54.62
    mesitylene 6.63
    ε-caprolactone 48.64
    p-cymene 8.66
    epichlorohydrin 79.77
    1,1,1-trichloroethane 35.57
    2-aminoethanol 161.88
    morpholine-4-carbaldehyde 115.95
    sulfolane 83.66
    2,2,4-trimethylpentane 3.36
    2-methyltetrahydrofuran 55.95
    n-hexyl acetate 26.53
    isooctane 2.1
    2-(2-butoxyethoxy)ethanol 71.11
    sec-butyl acetate 15.77
    tert-butyl acetate 23.2
    decalin 1.85
    glycerin 142.01
    diglyme 106.21
    acrylic acid 113.38
    isopropyl myristate 10.12
    n-butyric acid 106.06
    acetyl acetate 23.57
    di(2-ethylhexyl) phthalate 19.27
    ethyl propionate 19.19
    nitromethane 174.88
    1,2-diethoxyethane 33.38
    benzonitrile 34.16
    trioctyl phosphate 12.36
    1-bromopropane 17.17
    gamma-valerolactone 101.41
    n-decanol 15.33
    triethyl phosphate 13.95
    4-methyl-2-pentanol 31.49
    propionitrile 48.52
    vinylene carbonate 55.94
    1,1,2-trichlorotrifluoroethane 115.36
    DMS 22.39
    cumene 7.0
    2-octanol 19.53
    2-hexanone 28.91
    octyl acetate 16.08
    limonene 11.98
    1,2-dimethoxyethane 74.05
    ethyl orthosilicate 14.59
    tributyl phosphate 13.95
    diacetone alcohol 55.91
    N,N-dimethylaniline 25.42
    acrylonitrile 66.7
    aniline 39.86
    1,3-propanediol 126.83
    bromobenzene 13.84
    dibromomethane 35.49
    1,1,2,2-tetrachloroethane 56.5
    2-methyl-cyclohexyl acetate 21.41
    tetrabutyl urea 19.08
    diisobutyl methanol 14.11
    2-phenylethanol 40.19
    styrene 7.52
    dioctyl adipate 16.76
    dimethyl sulfate 47.4
    ethyl butyrate 21.4
    methyl lactate 51.41
    butyl lactate 29.4
    diethyl carbonate 14.82
    propanediol butyl ether 62.68
    triethyl orthoformate 17.71
    p-tert-butyltoluene 8.25
    methyl 4-tert-butylbenzoate 36.06
    morpholine 80.16
    tert-butylamine 45.25
    n-dodecanol 11.27
    dimethoxymethane 70.81
    ethylene carbonate 38.54
    cyrene 53.21
    2-ethoxyethyl acetate 36.24
    2-ethylhexyl acetate 20.3
    1,2,4-trichlorobenzene 28.72
    4-methylpyridine 50.82
    dibutyl ether 13.98
    2,6-dimethyl-4-heptanol 14.11
    DEF 60.27
    dimethyl isosorbide 58.94
    tetrachloroethylene 49.35
    eugenol 45.97
    triacetin 32.34
    span 80 46.37
    1,4-butanediol 72.79
    1,1-dichloroethane 36.97
    2-methyl-1-pentanol 60.22
    methyl formate 91.16
    2-methyl-1-butanol 78.48
    n-decane 1.86
    butyronitrile 46.62
    3,7-dimethyl-1-octanol 24.02
    1-chlorooctane 7.26
    1-chlorotetradecane 3.2
    n-nonane 1.71
    undecane 1.41
    tert-butylcyclohexane 2.66
    cyclooctane 0.86
    cyclopentanol 53.88
    tetrahydropyran 34.44
    tert-amyl methyl ether 29.89
    2,5,8-trioxanonane 75.05
    1-hexene 9.34
    2-isopropoxyethanol 73.01
    2,2,2-trifluoroethanol 118.6
    methyl butyrate 31.18

    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