2-Mercaptopyridine

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  • Identifiers

    CAS number
    2637-34-5

    Molecular formula
    C5H5NS

    SMILES
    C1=CC(=S)NC=C1

    Safety labels

    Irritant
    Irritant

  • Odor profile

    Fragrance
    Sulfurous 66.9%
    Burnt 55.95%
    Garlic 46.14%
    Pungent 43.69%
    Meaty 40.27%
    Alliaceous 38.69%
    Roasted 38.54%
    Nutty 38.24%
    Onion 34.77%
    Coffee 30.65%

     

    Flavor
    Bitter 43.69%
    Nutty 31.82%
    Sulfur 31.4%
    Pungent 28.25%
    Horseradish 24.58%
    Ethereal 23.74%
    Medical 21.74%
    Burnt sugar 21.65%
    Penetrating 21.61%
    Fragrant 21.28%

     

    Odor impact est.
    Low

  • Properties

    XLogP3-AA
    -0.1

    pKa est.
    8.57 (weak base)

    Molecular weight
    111.17 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Ultra slow

    Boiling point est.
    300°C

    Flash point

    • 83.53 ˚C est.

  • Synonyms

    • 2-Mercaptopyridine
    • 2637-34-5
    • 2-Thiopyridine
    • 2(1H)-PYRIDINETHIONE
    • 2-Thiopyridone
    • EE982KT952
    • DTXSID9062568
    • pyridine-2-thione
    • RefChem:474046
    • DTXCID5037492
    • 220-131-9
    • 946-524-1
    • Pyridine-2-thiol
    • 2-Pyridinethiol
    • 73018-10-7
    • 1H-pyridine-2-thione
    • Pyridinethione
    • Pyrid-2-thione
    • 2-Pyridyl mercaptan
    • 2-pyridylthiol
    • 1,2-dihydropyridine-2-thione
    • 2-Pyridinethione
    • pyridine-2(1H)-thione
    • C5H5NS
    • 2-pyridinylthiol
    • Alrithiol-2
    • MFCD00006285
    • 2-Mercapto pyridine
    • 29468-20-0
    • CHEBI:45223
    • Thiopyridone-2
    • Thiopyridone-2 [French]
    • 2-Pyridinethiol; 2-Pyridinethione; 2-Pyridyl mercaptan; 2-Pyridylthiol; 2-Sulfanylpyridine
    • NSC 41337
    • PYS
    • 2-mercapto-pyridine
    • EINECS 220-131-9
    • thioxopyridine
    • mercaptopyridine
    • UNII-EE982KT952
    • 2-thioxopyridine
    • pyridin-2-thiol
    • pyridine-2-thio
    • Pridine-2-thiol
    • Thio-2-pyridine
    • I+/--Thiopyridon
    • EINECS 249-657-7
    • pyridine, 2-mercapto-
    • Pyridin-2(1H)-thione
    • WLN: T6NJ BSH
    • Epitope ID:120365
    • SCHEMBL38243
    • SCHEMBL54576
    • MERCAPTOPYRIDINE, 2-
    • 29467-96-7
    • SCHEMBL143433
    • SCHEMBL421873
    • SCHEMBL3062854
    • SCHEMBL4466845
    • SCHEMBL4470294
    • SCHEMBL4477763
    • SCHEMBL6272432
    • SCHEMBL7333734
    • SCHEMBL7361437
    • SCHEMBL7453608
    • SCHEMBL8018779
    • CHEMBL1235541
    • SCHEMBL11350464
    • 2-mercaptopyridine (thione form)
    • BB_SC-13014
    • NSC41337
    • EBC-48212
    • NSC-41337
    • SBB058593
    • STL281380
    • AKOS000120194
    • AKOS003596823
    • DB03329
    • FM07088
    • PS-6210
    • PD007080
    • SY009099
    • 2-Mercaptopyridine, ReagentPlus(R), 99%
    • DB-015976
    • CS-0020126
    • M0246
    • NS00028094
    • ST50701362
    • EN300-21547
    • E81838
    • A818409
    • A837693
    • F023265
    • 2-Mercaptopyridine, Vetec(TM) reagent grade, 98%
    • Q15274000
    • F9995-0226
    • Z203045372
    • 2637-34-5

  • Applications

    2-Mercaptopyridine (CAS 2637-34-5) is principally used as a synthetic building block to introduce a thiol group on a pyridine ring, enabling the preparation of sulfur-containing heterocycles and various pharmaceutical intermediates. In coordination chemistry and catalysis, it serves as a ligand/chelating agent for transition metals, forming complexes used in research and materials applications. It also functions as a precursor for additional functionalization to create sulfur-containing ligands and cross-coupling partners. Given the thiol group’s affinity for metal surfaces, it is employed as a surface-functionalization reagent for coatings and electronic materials, and can participate in thiol-ene type polymer crosslinking to form network polymers. Collectively, these uses span industrial manufacturing, coatings, electronics, and materials science, with formulation constraints and regulatory considerations.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 132.27
    methanol 171.13
    isopropanol 79.16
    water 1.28
    ethyl acetate 109.04
    n-propanol 88.56
    acetone 259.99
    n-butanol 76.17
    acetonitrile 127.42
    DMF 284.22
    toluene 18.33
    isobutanol 48.64
    1,4-dioxane 163.31
    methyl acetate 143.86
    THF 251.24
    2-butanone 173.99
    n-pentanol 58.67
    sec-butanol 57.33
    n-hexane 0.55
    ethylene glycol 40.43
    NMP 148.91
    cyclohexane 1.03
    DMSO 407.66
    n-butyl acetate 79.58
    n-octanol 17.79
    chloroform 76.64
    n-propyl acetate 65.16
    acetic acid 136.63
    dichloromethane 59.65
    cyclohexanone 110.92
    propylene glycol 44.3
    isopropyl acetate 43.63
    DMAc 258.05
    2-ethoxyethanol 125.3
    isopentanol 56.32
    n-heptane 2.61
    ethyl formate 75.41
    1,2-dichloroethane 47.98
    n-hexanol 47.96
    2-methoxyethanol 201.98
    isobutyl acetate 36.41
    tetrachloromethane 8.68
    n-pentyl acetate 37.83
    transcutol 329.24
    n-heptanol 23.9
    ethylbenzene 6.37
    MIBK 44.79
    2-propoxyethanol 113.45
    tert-butanol 84.9
    MTBE 51.09
    2-butoxyethanol 61.04
    propionic acid 86.56
    o-xylene 11.52
    formic acid 69.85
    diethyl ether 56.99
    m-xylene 12.23
    p-xylene 9.93
    chlorobenzene 28.61
    dimethyl carbonate 47.12
    n-octane 0.89
    formamide 113.21
    cyclopentanone 176.16
    2-pentanone 105.51
    anisole 41.8
    cyclopentyl methyl ether 58.7
    gamma-butyrolactone 176.28
    1-methoxy-2-propanol 126.95
    pyridine 115.03
    3-pentanone 67.63
    furfural 160.09
    n-dodecane 1.01
    diethylene glycol 107.26
    diisopropyl ether 11.72
    tert-amyl alcohol 60.56
    acetylacetone 112.81
    n-hexadecane 1.12
    acetophenone 45.06
    methyl propionate 94.1
    isopentyl acetate 50.32
    trichloroethylene 115.09
    n-nonanol 16.73
    cyclohexanol 32.37
    benzyl alcohol 44.86
    2-ethylhexanol 26.4
    isooctanol 18.91
    dipropyl ether 32.64
    1,2-dichlorobenzene 23.35
    ethyl lactate 32.03
    propylene carbonate 77.02
    n-methylformamide 155.3
    2-pentanol 40.83
    n-pentane 1.02
    1-propoxy-2-propanol 77.18
    1-methoxy-2-propyl acetate 73.34
    2-(2-methoxypropoxy) propanol 66.28
    mesitylene 6.8
    ε-caprolactone 96.43
    p-cymene 10.29
    epichlorohydrin 168.88
    1,1,1-trichloroethane 40.67
    2-aminoethanol 65.49
    morpholine-4-carbaldehyde 188.8
    sulfolane 160.25
    2,2,4-trimethylpentane 1.4
    2-methyltetrahydrofuran 114.06
    n-hexyl acetate 36.68
    isooctane 1.25
    2-(2-butoxyethoxy)ethanol 88.29
    sec-butyl acetate 34.11
    tert-butyl acetate 43.62
    decalin 1.06
    glycerin 77.13
    diglyme 160.56
    acrylic acid 75.85
    isopropyl myristate 16.24
    n-butyric acid 98.86
    acetyl acetate 53.31
    di(2-ethylhexyl) phthalate 21.91
    ethyl propionate 42.05
    nitromethane 289.8
    1,2-diethoxyethane 89.16
    benzonitrile 53.85
    trioctyl phosphate 14.63
    1-bromopropane 20.99
    gamma-valerolactone 231.9
    n-decanol 13.51
    triethyl phosphate 20.44
    4-methyl-2-pentanol 23.98
    propionitrile 78.52
    vinylene carbonate 76.45
    1,1,2-trichlorotrifluoroethane 111.36
    DMS 40.47
    cumene 6.24
    2-octanol 13.67
    2-hexanone 63.96
    octyl acetate 22.1
    limonene 14.42
    1,2-dimethoxyethane 153.66
    ethyl orthosilicate 20.6
    tributyl phosphate 18.31
    diacetone alcohol 74.15
    N,N-dimethylaniline 25.93
    acrylonitrile 94.02
    aniline 46.43
    1,3-propanediol 93.23
    bromobenzene 21.02
    dibromomethane 30.93
    1,1,2,2-tetrachloroethane 77.99
    2-methyl-cyclohexyl acetate 29.39
    tetrabutyl urea 25.9
    diisobutyl methanol 16.21
    2-phenylethanol 42.7
    styrene 10.18
    dioctyl adipate 27.4
    dimethyl sulfate 75.12
    ethyl butyrate 43.61
    methyl lactate 50.72
    butyl lactate 35.96
    diethyl carbonate 27.85
    propanediol butyl ether 56.55
    triethyl orthoformate 31.37
    p-tert-butyltoluene 10.56
    methyl 4-tert-butylbenzoate 37.79
    morpholine 171.98
    tert-butylamine 33.27
    n-dodecanol 11.04
    dimethoxymethane 147.49
    ethylene carbonate 58.06
    cyrene 59.39
    2-ethoxyethyl acetate 66.72
    2-ethylhexyl acetate 38.73
    1,2,4-trichlorobenzene 35.3
    4-methylpyridine 94.13
    dibutyl ether 21.64
    2,6-dimethyl-4-heptanol 16.21
    DEF 97.03
    dimethyl isosorbide 92.48
    tetrachloroethylene 42.34
    eugenol 45.13
    triacetin 47.66
    span 80 46.69
    1,4-butanediol 42.98
    1,1-dichloroethane 51.11
    2-methyl-1-pentanol 45.06
    methyl formate 105.76
    2-methyl-1-butanol 51.11
    n-decane 1.4
    butyronitrile 76.95
    3,7-dimethyl-1-octanol 20.88
    1-chlorooctane 7.62
    1-chlorotetradecane 3.69
    n-nonane 1.19
    undecane 1.16
    tert-butylcyclohexane 1.42
    cyclooctane 0.54
    cyclopentanol 48.17
    tetrahydropyran 92.92
    tert-amyl methyl ether 36.59
    2,5,8-trioxanonane 116.12
    1-hexene 4.69
    2-isopropoxyethanol 81.71
    2,2,2-trifluoroethanol 44.87
    methyl butyrate 58.52

    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