Thiolactic acid

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  • Identifiers

    CAS number
    79-42-5

    Molecular formula
    C3H6O2S

    SMILES
    CC(C(=O)O)S

    Safety labels

    Corrosive
    Corrosive

    Acute Toxic
    Acute Toxic

  • Odor profile

    Sulfurous 90.42%
    Meaty 80.96%
    Roasted 64.28%
    Savory 57.34%
    Onion 45.11%
    Cheesy 38.89%
    Alliaceous 37.61%
    Cooked 36.89%
    Tropical 31.75%
    Garlic 31.65%

    Scent© AI

  • Properties

    XLogP3-AA
    0.5

    Molecular weight
    106.15 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Moderate

    Melting point expt.

    • 12 °C

    Boiling point

    • 117.00 °C. @ 16.00 mm Hg

    Flash point est.
    87.01 ˚C

    Solubility expt.

    • miscible in water, alcohol, ether and acetone
    • 1 mL in 1 mL 95% alcohol (in ethanol)

  • Synonyms

    • 2-Mercaptopropionic acid
    • Thiolactic acid
    • 79-42-5
    • 2-Sulfanylpropanoic acid
    • 2-Mercaptopropanoic acid
    • 2-Thiolactic acid
    • 2-Thiolpropionic acid
    • alpha-Mercaptopropionic acid
    • PROPANOIC ACID, 2-MERCAPTO-
    • alpha-Mercaptopropanoic acid
    • Propionic acid, 2-mercapto-
    • FEMA No. 3180
    • EINECS 201-206-5
    • UN2936
    • BRN 0506218
    • O5U6967KGF
    • CHEBI:47872
    • 2-mercapto-propionic acid
    • THIOLACTIC ACID [MI]
    • THIOLACTIC ACID [FHFI]
    • DTXSID80861636
    • 4-03-00-00682 (Beilstein Handbook Reference)
    • 2-mercapto propionic acid
    • UNII-O5U6967KGF
    • 2Thiolactic acid
    • Rac-Thiolactic Acid
    • 2Thiolpropionic acid
    • MFCD00004862
    • Thiolactic acid [UN2936] [Poison]
    • 2mercaptopropanoic acid
    • mercapto-propionic acid
    • Thiolactic acid, 95%
    • alphaMercaptopropanoic acid
    • alphaMercaptopropionic acid
    • Propanoic acid, 2mercapto
    • Propionic acid, 2mercapto
    • 2-Mercapto-Propanoic acid
    • alpha -mercaptopropanoic acid
    • alpha -mercaptopropionic acid
    • SCHEMBL15864
    • .alpha.-Mercaptopropanoic acid
    • .alpha.-Mercaptopropionic acid
    • THIOLACTIC ACID [INCI]
    • CHEMBL2158192
    • FEMA 3180
    • DTXCID30810533
    • STR01228
    • BBL011561
    • STL146731
    • AKOS000120478
    • AKOS017278454
    • UN 2936
    • 2-Mercaptopropionic acid, >=95%, FG
    • Thiolactic acid [UN2936] [Poison]
    • (+/-)-2-MERCAPTOPROPIONIC ACID
    • PD123987
    • 2-Mercaptopropionic acid, analytical standard
    • M0060
    • NS00007987
    • EN300-20156
    • E78835
    • Q27120833
    • F2191-0225
    • Z104477082
    • 201-206-5

  • Applications

    2-Mercaptopropionic acid (thiolactic acid, CAS 79-42-5) is a versatile organosulfur compound whose –SH group makes it valuable across many fields: it acts as a chain-transfer agent in free-radical polymerizations to tailor molecular weight of styrene, acrylate and methacrylate resins; serves as a curing modifier and thermal stabilizer for PVC by scavenging radicals; functions in cold wave lotions as a mild reducing agent that reshapes hair keratin; is an intermediate for synthesizing pharmaceuticals, pesticides and surfactants because both thiol and carboxyl moieties can be derivatized; is blended into epoxy systems to enhance adhesion, flexibility and chemical resistance, and is employed as a corrosion inhibitor and chelating agent for heavy-metal recovery in wastewater treatment; in analytical chemistry it is used to complex and quantify copper, iron and molybdenum ions and to fine-tune mobile-phase pH in chromatography.

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 83.8
    methanol 148.21
    isopropanol 39.08
    water 403.4
    ethyl acetate 6.25
    n-propanol 36.37
    acetone 32.51
    n-butanol 30.04
    acetonitrile 7.35
    DMF 97.89
    toluene 1.08
    isobutanol 22.04
    1,4-dioxane 19.66
    methyl acetate 8.82
    THF 31.08
    2-butanone 12.58
    n-pentanol 22.06
    sec-butanol 24.97
    n-hexane 1.44
    ethylene glycol 106.06
    NMP 76.71
    cyclohexane 1.04
    DMSO 85.98
    n-butyl acetate 5.22
    n-octanol 15.66
    chloroform 3.32
    n-propyl acetate 6.08
    acetic acid 116.02
    dichloromethane 3.35
    cyclohexanone 15.74
    propylene glycol 64.8
    isopropyl acetate 6.76
    DMAc 70.83
    2-ethoxyethanol 70.07
    isopentanol 28.01
    n-heptane 1.38
    ethyl formate 16.43
    1,2-dichloroethane 3.1
    n-hexanol 15.69
    2-methoxyethanol 118.83
    isobutyl acetate 4.13
    tetrachloromethane 2.38
    n-pentyl acetate 10.35
    transcutol 107.55
    n-heptanol 18.53
    ethylbenzene 1.6
    MIBK 12.33
    2-propoxyethanol 42.27
    tert-butanol 48.6
    MTBE 10.63
    2-butoxyethanol 47.16
    propionic acid 32.19
    o-xylene 2.36
    formic acid 226.96
    diethyl ether 6.22
    m-xylene 2.0
    p-xylene 2.32
    chlorobenzene 1.19
    dimethyl carbonate 7.48
    n-octane 0.92
    formamide 201.2
    cyclopentanone 24.89
    2-pentanone 12.73
    anisole 5.8
    cyclopentyl methyl ether 9.52
    gamma-butyrolactone 28.35
    1-methoxy-2-propanol 68.06
    pyridine 6.32
    3-pentanone 6.02
    furfural 35.52
    n-dodecane 0.76
    diethylene glycol 74.37
    diisopropyl ether 3.47
    tert-amyl alcohol 37.13
    acetylacetone 20.83
    n-hexadecane 0.75
    acetophenone 9.36
    methyl propionate 7.35
    isopentyl acetate 6.09
    trichloroethylene 5.08
    n-nonanol 13.71
    cyclohexanol 13.18
    benzyl alcohol 11.8
    2-ethylhexanol 8.97
    isooctanol 14.78
    dipropyl ether 4.28
    1,2-dichlorobenzene 1.9
    ethyl lactate 11.05
    propylene carbonate 16.18
    n-methylformamide 63.41
    2-pentanol 17.1
    n-pentane 1.46
    1-propoxy-2-propanol 24.69
    1-methoxy-2-propyl acetate 10.38
    2-(2-methoxypropoxy) propanol 41.3
    mesitylene 2.3
    ε-caprolactone 17.86
    p-cymene 2.36
    epichlorohydrin 17.81
    1,1,1-trichloroethane 2.39
    2-aminoethanol 110.85
    morpholine-4-carbaldehyde 68.51
    sulfolane 46.8
    2,2,4-trimethylpentane 1.25
    2-methyltetrahydrofuran 15.4
    n-hexyl acetate 12.99
    isooctane 1.16
    2-(2-butoxyethoxy)ethanol 59.26
    sec-butyl acetate 4.37
    tert-butyl acetate 12.07
    decalin 0.91
    glycerin 123.5
    diglyme 74.72
    acrylic acid 40.94
    isopropyl myristate 5.71
    n-butyric acid 30.55
    acetyl acetate 7.34
    di(2-ethylhexyl) phthalate 11.3
    ethyl propionate 4.58
    nitromethane 70.37
    1,2-diethoxyethane 12.7
    benzonitrile 4.03
    trioctyl phosphate 8.95
    1-bromopropane 1.62
    gamma-valerolactone 45.71
    n-decanol 10.08
    triethyl phosphate 4.65
    4-methyl-2-pentanol 14.86
    propionitrile 3.96
    vinylene carbonate 12.85
    1,1,2-trichlorotrifluoroethane 37.53
    DMS 7.6
    cumene 2.39
    2-octanol 11.21
    2-hexanone 9.42
    octyl acetate 8.73
    limonene 3.44
    1,2-dimethoxyethane 51.35
    ethyl orthosilicate 4.82
    tributyl phosphate 8.0
    diacetone alcohol 40.92
    N,N-dimethylaniline 8.7
    acrylonitrile 6.54
    aniline 5.11
    1,3-propanediol 99.08
    bromobenzene 0.74
    dibromomethane 2.27
    1,1,2,2-tetrachloroethane 5.28
    2-methyl-cyclohexyl acetate 7.97
    tetrabutyl urea 12.72
    diisobutyl methanol 6.9
    2-phenylethanol 11.01
    styrene 1.44
    dioctyl adipate 10.46
    dimethyl sulfate 16.67
    ethyl butyrate 4.78
    methyl lactate 20.47
    butyl lactate 16.69
    diethyl carbonate 3.3
    propanediol butyl ether 55.84
    triethyl orthoformate 4.83
    p-tert-butyltoluene 2.63
    methyl 4-tert-butylbenzoate 22.01
    morpholine 27.35
    tert-butylamine 20.09
    n-dodecanol 7.19
    dimethoxymethane 32.92
    ethylene carbonate 9.25
    cyrene 40.55
    2-ethoxyethyl acetate 15.55
    2-ethylhexyl acetate 4.17
    1,2,4-trichlorobenzene 2.51
    4-methylpyridine 5.99
    dibutyl ether 5.43
    2,6-dimethyl-4-heptanol 6.9
    DEF 21.01
    dimethyl isosorbide 39.34
    tetrachloroethylene 6.4
    eugenol 27.93
    triacetin 17.69
    span 80 36.2
    1,4-butanediol 50.67
    1,1-dichloroethane 2.0
    2-methyl-1-pentanol 21.82
    methyl formate 41.53
    2-methyl-1-butanol 22.57
    n-decane 1.11
    butyronitrile 5.77
    3,7-dimethyl-1-octanol 12.62
    1-chlorooctane 2.85
    1-chlorotetradecane 1.5
    n-nonane 1.03
    undecane 0.89
    tert-butylcyclohexane 1.18
    cyclooctane 0.73
    cyclopentanol 21.8
    tetrahydropyran 7.87
    tert-amyl methyl ether 10.18
    2,5,8-trioxanonane 61.75
    1-hexene 2.87
    2-isopropoxyethanol 38.65
    2,2,2-trifluoroethanol 62.96
    methyl butyrate 8.83

    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