Methanethiol

Overview IFRA Botanical Request a quote

  • Identifiers

    CAS number
    74-93-1

    Molecular formula
    CH4S

    SMILES
    CS

    Safety labels

    Flammable
    Flammable

    Compressed Gas
    Compressed Gas

    Acute Toxic
    Acute Toxic

    Environmental Hazard
    Environmental

  • Odor profile

    Sulfurous 84.84%
    Garlic 69.14%
    Onion 68.55%
    Meaty 64.97%
    Vegetable 61.74%
    Alliaceous 58.07%
    Cabbage 53.82%
    Savory 50.4%
    Creamy 43.18%
    Cooked 42.71%

    Scent© AI

    Odor threshold

    • Odor Threshold Low: 0.0000002 [ppm]. Odor Threshold High: 0.04 [ppm]. Detection odor threshold from AIHA (mean = 0.00054 ppm)
    • 0.0021 ppm (purity not specified)
    • High odor threshold= 0.0820 mg/m (purity not specified)

  • Properties

    XLogP3-AA
    0.5

    pKa est.
    10.26 (weak base)

    Molecular weight
    48.11 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Ultra fast

    Melting point expt.

    • -189.4 °F (EPA, 1998)
    • -123 °C
    • -189.4 °F
    • -186 °F

    Boiling point

    • 42.7 °F at 760 mmHg (EPA, 1998)
    • 5.95 °C at 760 mm Hg
    • 6.10 to 6.20 °C. @ 727.00 mm Hg
    • 6 °C
    • 42.7 °F
    • 43 °F

    Flash point est.
    -16.49 ˚C

    Flash point expt.

    • 0 °F (EPA, 1998)
    • -18 °C
    • < -17.78 °Celsius, open cup
    • 0 °F (Open cup) /Liquid/
    • 0 °F (LESS THAN -18 °C) (OPEN CUP)
    • Flammable gas
    • 0 °F
    • NA (Gas) (oc) 0 °F (Liquid)

    Solubility expt.

    • 2 % (NIOSH, 2024)
    • Soluble in alcohol and ether; slightly soluble in chloroform
    • Soluble in petroleum naptha
    • In water, 15,400 mg/L at 25 °C
    • Very soluble in alcohol or in ether; soluble in water (23.3 g/L at 20 °C)
    • 15.4 mg/mL at 25 °C
    • Solubility in water, g/100ml at 20 °C: 2.3
    • 2.4 g/100 ml water; soluble in alcohol, ether, organic solvents
    • 2%

  • Synonyms

    • methanethiol
    • METHYL MERCAPTAN
    • Methylmercaptan
    • Mercaptomethane
    • 74-93-1
    • Methyl sulfhydrate
    • Methanthiol
    • Thiomethanol
    • Thiomethyl alcohol
    • Metilmercaptano
    • Methvtiolo
    • Thiomethane
    • Methylmercaptaan
    • Mercaptan methylique
    • Methaanthiol
    • Methanethiole
    • Methanthiol [German]
    • methyl-mercaptan
    • CH3SH
    • FEMA No. 2716
    • Methyl thioalcohol
    • Methyl mercaptan (natural)
    • RCRA waste number U153
    • HSDB 813
    • methyl thiol
    • methyl-thiol
    • EINECS 200-822-1
    • MeSH
    • methylsulfanium
    • UN1064
    • UNII-2X8406WW9I
    • UN 1064
    • BRN 1696840
    • METHANETHIOL [MI]
    • METHYL MERCAPTAN [FHFI]
    • METHYL MERCAPTAN [HSDB]
    • DTXSID5026382
    • CHEBI:16007
    • EC 200-822-1
    • 2X8406WW9I
    • 4-01-00-01273 (Beilstein Handbook Reference)
    • METHANTHIOL (GERMAN)
    • Methaanthiol [Dutch]
    • Methvtiolo [Italian]
    • Methylmercaptaan [Dutch]
    • Metilmercaptano [Italian]
    • Metilmercaptano [Spanish]
    • Mercaptan methylique [French]
    • RCRA waste no. U153
    • methylsulfanyl
    • methane thiol
    • (methyl)sulfane
    • Methylthioalcohol
    • a methyl thioether
    • sulfonium methylide
    • Methanethiol, purum
    • METHANEETHIOL
    • Methanethiol (OSHA)
    • Methanethiol, 98.0%
    • Methanethiol, >=98.0%
    • DTXCID406382
    • Methyl mercaptan (ACGIH:OSHA)
    • DTXSID10168842
    • DTXSID60992376
    • NSC229573
    • AKOS009157032
    • METHYL MERCAPTAN (METHANETHIOL)
    • NSC-229573
    • Methyl mercaptan [UN1064] [Poison gas]
    • NS00020025
    • C00409
    • Q409309
    • 17719-48-1
    • Z22

  • Applications

    Methanethiol (methyl mercaptan, CAS 74-93-1) is used chiefly as an intermediate to produce DL‑methionine for animal nutrition; as a methylthio building block in the synthesis of pharmaceuticals and agrochemicals; as a precursor to dimethyl sulfide and dimethyl disulfide (DMDS) for presulfiding and activation of refining catalysts; and is occasionally employed as a warning odorant for natural gas and LPG; it also features in surface science for forming self‑assembled monolayers on gold, as a chain‑transfer agent in radical polymerizations, and at trace levels as a character‑impact note in certain natural food flavors.

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 171.77
    methanol 250.43
    isopropanol 86.48
    water 1.22
    ethyl acetate 50.28
    n-propanol 105.99
    acetone 163.91
    n-butanol 99.06
    acetonitrile 78.87
    DMF 183.68
    toluene 17.03
    isobutanol 58.87
    1,4-dioxane 105.68
    methyl acetate 55.85
    THF 194.03
    2-butanone 70.05
    n-pentanol 56.82
    sec-butanol 54.24
    n-hexane 9.51
    ethylene glycol 68.94
    NMP 197.81
    cyclohexane 22.49
    DMSO 437.64
    n-butyl acetate 98.32
    n-octanol 30.72
    chloroform 153.52
    n-propyl acetate 45.31
    acetic acid 272.64
    dichloromethane 144.34
    cyclohexanone 164.04
    propylene glycol 48.29
    isopropyl acetate 26.63
    DMAc 66.15
    2-ethoxyethanol 69.05
    isopentanol 55.47
    n-heptane 21.1
    ethyl formate 73.8
    1,2-dichloroethane 102.14
    n-hexanol 80.43
    2-methoxyethanol 157.02
    isobutyl acetate 25.65
    tetrachloromethane 40.61
    n-pentyl acetate 44.97
    transcutol 190.53
    n-heptanol 38.95
    ethylbenzene 9.13
    MIBK 25.04
    2-propoxyethanol 100.48
    tert-butanol 71.89
    MTBE 25.01
    2-butoxyethanol 63.6
    propionic acid 114.55
    o-xylene 10.76
    formic acid 122.2
    diethyl ether 40.39
    m-xylene 10.13
    p-xylene 13.22
    chlorobenzene 55.97
    dimethyl carbonate 20.59
    n-octane 6.45
    formamide 141.39
    cyclopentanone 207.88
    2-pentanone 58.79
    anisole 24.49
    cyclopentyl methyl ether 60.34
    gamma-butyrolactone 225.91
    1-methoxy-2-propanol 78.83
    pyridine 141.94
    3-pentanone 36.68
    furfural 202.72
    n-dodecane 4.32
    diethylene glycol 98.8
    diisopropyl ether 9.64
    tert-amyl alcohol 45.68
    acetylacetone 69.15
    n-hexadecane 4.66
    acetophenone 34.19
    methyl propionate 42.7
    isopentyl acetate 59.38
    trichloroethylene 173.74
    n-nonanol 26.03
    cyclohexanol 75.38
    benzyl alcohol 38.48
    2-ethylhexanol 43.81
    isooctanol 27.95
    dipropyl ether 50.88
    1,2-dichlorobenzene 51.88
    ethyl lactate 26.48
    propylene carbonate 105.9
    n-methylformamide 145.89
    2-pentanol 43.9
    n-pentane 12.62
    1-propoxy-2-propanol 83.78
    1-methoxy-2-propyl acetate 53.17
    2-(2-methoxypropoxy) propanol 45.34
    mesitylene 7.11
    ε-caprolactone 115.95
    p-cymene 16.97
    epichlorohydrin 135.45
    1,1,1-trichloroethane 68.49
    2-aminoethanol 87.23
    morpholine-4-carbaldehyde 140.59
    sulfolane 323.78
    2,2,4-trimethylpentane 3.45
    2-methyltetrahydrofuran 104.5
    n-hexyl acetate 48.0
    isooctane 3.19
    2-(2-butoxyethoxy)ethanol 74.11
    sec-butyl acetate 19.93
    tert-butyl acetate 27.26
    decalin 5.72
    glycerin 74.53
    diglyme 120.93
    acrylic acid 125.79
    isopropyl myristate 20.72
    n-butyric acid 144.35
    acetyl acetate 41.2
    di(2-ethylhexyl) phthalate 24.54
    ethyl propionate 27.57
    nitromethane 236.11
    1,2-diethoxyethane 61.37
    benzonitrile 67.04
    trioctyl phosphate 22.14
    1-bromopropane 55.45
    gamma-valerolactone 203.18
    n-decanol 20.3
    triethyl phosphate 22.48
    4-methyl-2-pentanol 19.4
    propionitrile 62.52
    vinylene carbonate 102.46
    1,1,2-trichlorotrifluoroethane 147.84
    DMS 31.74
    cumene 7.8
    2-octanol 22.88
    2-hexanone 44.03
    octyl acetate 27.1
    limonene 28.59
    1,2-dimethoxyethane 90.32
    ethyl orthosilicate 22.16
    tributyl phosphate 27.22
    diacetone alcohol 46.24
    N,N-dimethylaniline 18.82
    acrylonitrile 97.6
    aniline 48.73
    1,3-propanediol 111.59
    bromobenzene 44.4
    dibromomethane 109.4
    1,1,2,2-tetrachloroethane 124.47
    2-methyl-cyclohexyl acetate 37.88
    tetrabutyl urea 38.36
    diisobutyl methanol 24.86
    2-phenylethanol 50.76
    styrene 15.34
    dioctyl adipate 32.13
    dimethyl sulfate 42.57
    ethyl butyrate 55.16
    methyl lactate 36.79
    butyl lactate 42.36
    diethyl carbonate 31.78
    propanediol butyl ether 59.17
    triethyl orthoformate 36.54
    p-tert-butyltoluene 16.09
    methyl 4-tert-butylbenzoate 34.02
    morpholine 130.88
    tert-butylamine 44.38
    n-dodecanol 17.02
    dimethoxymethane 65.49
    ethylene carbonate 77.12
    cyrene 50.53
    2-ethoxyethyl acetate 50.24
    2-ethylhexyl acetate 47.68
    1,2,4-trichlorobenzene 54.75
    4-methylpyridine 86.19
    dibutyl ether 35.69
    2,6-dimethyl-4-heptanol 24.86
    DEF 64.18
    dimethyl isosorbide 78.69
    tetrachloroethylene 118.93
    eugenol 43.45
    triacetin 39.55
    span 80 58.77
    1,4-butanediol 41.94
    1,1-dichloroethane 68.02
    2-methyl-1-pentanol 34.19
    methyl formate 100.81
    2-methyl-1-butanol 48.75
    n-decane 6.62
    butyronitrile 76.09
    3,7-dimethyl-1-octanol 27.07
    1-chlorooctane 20.6
    1-chlorotetradecane 9.13
    n-nonane 6.99
    undecane 5.11
    tert-butylcyclohexane 5.16
    cyclooctane 5.91
    cyclopentanol 101.58
    tetrahydropyran 106.7
    tert-amyl methyl ether 18.39
    2,5,8-trioxanonane 88.47
    1-hexene 25.14
    2-isopropoxyethanol 37.45
    2,2,2-trifluoroethanol 71.78
    methyl butyrate 49.45

    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

Botanical

Name CAS Botanical Proportion
Onion (shallot) 8002-72-0 Allium cepa L., Aggregatum g., fam. Liliaceae 0.65%
Carob bean extract 1 9000-40-2 Ceratonia siliqua L., fam. Leguminoseae 0.04%
Parsley leaf (Germany) 2a 8000-68-8 Petroselinum crispun (Miller) A.W. Hill cv Hamburger Schnitt,fam. Apiaceae 0.04%
Parsley leaf (Germany) 2b 800-68-8 Petroselinum crispun (Miller) A.W. Hill cv Mooskrause, fam. Apiaceae 0.04%
Pineapple pulp Ananas comosus (L.) Merr., fam. Bromeliaceae 0.12%