2-Thiophenecarboxylic acid

Overview IFRA Request a quote

  • Identifiers

    CAS number
    527-72-0

    Molecular formula
    C5H4O2S

    SMILES
    C1=CSC(=C1)C(=O)O

    Safety labels

    Irritant
    Irritant

  • Odor profile

    Fragrance
    Sulfurous 63.49%
    Roasted 49.29%
    Odorless 48.41%
    Meaty 46.36%
    Burnt 45.36%
    Coffee 35.22%
    Cooked 34.24%
    Savory 33.99%
    Nutty 32.0%
    Caramellic 28.7%

     

    Flavor
    Odorless 43.98%
    Nutty 39.41%
    Sour 38.58%
    Faint 29.63%
    Sulfur 29.18%
    Bread 28.28%
    Mild 27.4%
    Musty 24.46%
    Popcorn 24.35%
    Urine 23.68%

     

    Odor impact est.
    High

  • Properties

    XLogP3-AA
    1.6

    pKa est.
    6.66 (neutral)

    Molecular weight
    128.15 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Ultra slow

    Boiling point est.
    269°C

    Flash point

    • 103.81 ˚C est.

  • Synonyms

    • 2-Thiophenecarboxylic acid
    • 527-72-0
    • 2-Thenoic acid
    • 2-Carboxythiophene
    • 2-Thienylcarboxylic acid
    • Tenoic acid
    • 2-TCA
    • Thenoic acid
    • NSC 2188
    • EINECS 208-423-4
    • Rhinotrophyl (TN)
    • BRN 0110150
    • Tenoic acid (DCF)
    • AI3-16118
    • NSC-2188
    • Thiophene-2-carbixylic acid
    • THENOIC ACID [WHO-DD]
    • DTXSID2060177
    • 5-18-06-00158 (Beilstein Handbook Reference)
    • 2-THIOPHENECARBOXYLIC ACID [MI]
    • Rhinotrophyl
    • 2Carboxythiophene
    • 2Thenoic acid
    • 2Thiophenic acid
    • Thiophene2carboxylate
    • 2Thienylcarboxylic acid
    • Thiophene2carboxylic acid
    • RefChem:483774
    • alphaThiophenecarboxylic acid
    • DTXCID7041259
    • 208-423-4
    • THIOPHENE-2-CARBOXYLIC ACID
    • 2-Thiophenic acid
    • alpha-Thiophenecarboxylic acid
    • MFCD00005437
    • C5H4O2S
    • .alpha.-Thiophenecarboxylic acid
    • Thiophene Carboxylic Acid
    • 2-thiophene carboxylic acid
    • THIOPHENECARBOXYLIC ACID
    • 3FD00JX53J
    • CHEMBL1222314
    • 2-Thiophenecarboxylicacid
    • thiolcarboxylic acid
    • Thiophene-2-carboxylicAcid
    • UNII-3FD00JX53J
    • thienoic acid
    • 2-thienoic acid
    • 2hdq
    • 2-Thiophenecarboxylic Acid; 2-Carboxythiophene; 2-Thiophenic Acid; NSC 2188; alpha-Thiophenecarboxylic Acid
    • thiophencarboxylic acid
    • thienyl carboxylic acid
    • thiopene-2-carboxylic acid
    • thiophen-2-carboxylic acid
    • bmse000848
    • 2-thiophene-carboxylic acid
    • NCIOpen2_000991
    • SCHEMBL83000
    • BIDD:GT0592
    • SCHEMBL128322
    • SCHEMBL128650
    • SCHEMBL131874
    • SCHEMBL225933
    • orb3029875
    • CHEBI:71241
    • NSC2188
    • BDBM50324678
    • EBC-03072
    • SBB004241
    • STK362877
    • AKOS000119344
    • AC-4922
    • BS-3764
    • CS-W020070
    • FT62260
    • NCGC00188253-01
    • BP-20572
    • ST081377
    • SY001476
    • DB-000869
    • NS00032580
    • T0218
    • Thiophene-2-carboxylic acid; 2-Thenoic acid
    • EN300-16724
    • D08568
    • D70571
    • 2-Thiophenecarboxylic acid, ReagentPlus(R), 99%
    • AQ-738/40654023
    • F003042
    • Q2823319
    • F2191-0071
    • 2-Thiophenecarboxylic acid, Vetec(TM) reagent grade, 98%
    • 2-Thenoic Acid2-Thiophenic Acid Thiophene-2-carboxylic acid
    • 527-72-0

  • Applications

    2-Thiophenecarboxylic acid (CAS 527-72-0) is a versatile building block in the synthesis of thiophene-containing heterocycles, commonly used as an intermediate in pharmaceutical development and in agrochemical research. It can be converted to amide, ester, or other derivatives to support diverse synthetic routes toward heterocyclic frameworks. In the materials sector, it serves as a precursor for thiophene-based monomers and conjugated polymers used in organic electronics, sensors, and related coatings. It also provides routes to dye and pigment-related compounds and can be employed in coatings and inks after functionalization. In R&D contexts, it is valued as a flexible starting material for advanced heterocycle chemistry and catalysis studies, with usage governed by local regulations and formulation constraints.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 182.7
    methanol 227.44
    isopropanol 135.77
    water 5.79
    ethyl acetate 66.46
    n-propanol 117.74
    acetone 121.08
    n-butanol 105.05
    acetonitrile 25.91
    DMF 589.31
    toluene 5.84
    isobutanol 66.82
    1,4-dioxane 147.52
    methyl acetate 69.77
    THF 302.28
    2-butanone 83.86
    n-pentanol 108.65
    sec-butanol 92.29
    n-hexane 1.71
    ethylene glycol 100.54
    NMP 271.95
    cyclohexane 0.89
    DMSO 374.24
    n-butyl acetate 52.81
    n-octanol 83.42
    chloroform 9.31
    n-propyl acetate 62.74
    acetic acid 114.07
    dichloromethane 8.61
    cyclohexanone 84.77
    propylene glycol 83.21
    isopropyl acetate 64.12
    DMAc 211.07
    2-ethoxyethanol 270.74
    isopentanol 88.33
    n-heptane 3.98
    ethyl formate 50.44
    1,2-dichloroethane 13.72
    n-hexanol 95.85
    2-methoxyethanol 379.82
    isobutyl acetate 37.18
    tetrachloromethane 2.69
    n-pentyl acetate 67.76
    transcutol 658.91
    n-heptanol 71.91
    ethylbenzene 6.15
    MIBK 103.0
    2-propoxyethanol 234.53
    tert-butanol 152.32
    MTBE 58.74
    2-butoxyethanol 162.19
    propionic acid 76.72
    o-xylene 9.02
    formic acid 137.14
    diethyl ether 58.77
    m-xylene 12.57
    p-xylene 7.79
    chlorobenzene 8.57
    dimethyl carbonate 51.7
    n-octane 2.51
    formamide 225.21
    cyclopentanone 146.24
    2-pentanone 114.35
    anisole 46.68
    cyclopentyl methyl ether 94.48
    gamma-butyrolactone 188.38
    1-methoxy-2-propanol 343.38
    pyridine 41.12
    3-pentanone 49.83
    furfural 150.2
    n-dodecane 3.1
    diethylene glycol 225.69
    diisopropyl ether 27.48
    tert-amyl alcohol 99.96
    acetylacetone 133.07
    n-hexadecane 3.4
    acetophenone 53.87
    methyl propionate 75.13
    isopentyl acetate 46.59
    trichloroethylene 26.85
    n-nonanol 73.29
    cyclohexanol 52.04
    benzyl alcohol 56.76
    2-ethylhexanol 45.74
    isooctanol 56.96
    dipropyl ether 45.01
    1,2-dichlorobenzene 11.3
    ethyl lactate 67.57
    propylene carbonate 82.72
    n-methylformamide 213.77
    2-pentanol 99.57
    n-pentane 2.11
    1-propoxy-2-propanol 160.03
    1-methoxy-2-propyl acetate 95.69
    2-(2-methoxypropoxy) propanol 140.97
    mesitylene 11.71
    ε-caprolactone 96.32
    p-cymene 12.38
    epichlorohydrin 138.0
    1,1,1-trichloroethane 9.93
    2-aminoethanol 154.24
    morpholine-4-carbaldehyde 321.68
    sulfolane 233.64
    2,2,4-trimethylpentane 2.57
    2-methyltetrahydrofuran 123.45
    n-hexyl acetate 95.7
    isooctane 3.68
    2-(2-butoxyethoxy)ethanol 246.94
    sec-butyl acetate 45.92
    tert-butyl acetate 94.24
    decalin 2.07
    glycerin 159.67
    diglyme 316.38
    acrylic acid 76.82
    isopropyl myristate 45.69
    n-butyric acid 90.37
    acetyl acetate 36.27
    di(2-ethylhexyl) phthalate 38.0
    ethyl propionate 52.12
    nitromethane 174.53
    1,2-diethoxyethane 121.21
    benzonitrile 32.69
    trioctyl phosphate 36.42
    1-bromopropane 7.17
    gamma-valerolactone 248.27
    n-decanol 55.82
    triethyl phosphate 28.4
    4-methyl-2-pentanol 68.79
    propionitrile 27.08
    vinylene carbonate 62.65
    1,1,2-trichlorotrifluoroethane 123.87
    DMS 57.72
    cumene 8.69
    2-octanol 61.99
    2-hexanone 79.96
    octyl acetate 56.44
    limonene 17.71
    1,2-dimethoxyethane 238.13
    ethyl orthosilicate 27.99
    tributyl phosphate 38.82
    diacetone alcohol 180.78
    N,N-dimethylaniline 44.59
    acrylonitrile 41.14
    aniline 27.44
    1,3-propanediol 194.77
    bromobenzene 4.67
    dibromomethane 4.98
    1,1,2,2-tetrachloroethane 27.59
    2-methyl-cyclohexyl acetate 43.36
    tetrabutyl urea 59.23
    diisobutyl methanol 37.73
    2-phenylethanol 64.9
    styrene 6.55
    dioctyl adipate 56.56
    dimethyl sulfate 97.74
    ethyl butyrate 44.92
    methyl lactate 103.23
    butyl lactate 74.03
    diethyl carbonate 26.16
    propanediol butyl ether 185.58
    triethyl orthoformate 37.51
    p-tert-butyltoluene 13.97
    methyl 4-tert-butylbenzoate 90.32
    morpholine 194.41
    tert-butylamine 64.36
    n-dodecanol 40.68
    dimethoxymethane 270.62
    ethylene carbonate 48.58
    cyrene 133.78
    2-ethoxyethyl acetate 102.44
    2-ethylhexyl acetate 32.68
    1,2,4-trichlorobenzene 17.78
    4-methylpyridine 42.84
    dibutyl ether 52.97
    2,6-dimethyl-4-heptanol 37.73
    DEF 132.58
    dimethyl isosorbide 198.35
    tetrachloroethylene 18.59
    eugenol 111.64
    triacetin 91.11
    span 80 131.63
    1,4-butanediol 104.11
    1,1-dichloroethane 9.48
    2-methyl-1-pentanol 74.99
    methyl formate 132.93
    2-methyl-1-butanol 67.08
    n-decane 4.71
    butyronitrile 35.85
    3,7-dimethyl-1-octanol 58.48
    1-chlorooctane 21.67
    1-chlorotetradecane 9.96
    n-nonane 4.02
    undecane 3.76
    tert-butylcyclohexane 3.02
    cyclooctane 0.87
    cyclopentanol 88.45
    tetrahydropyran 70.81
    tert-amyl methyl ether 55.9
    2,5,8-trioxanonane 248.63
    1-hexene 8.61
    2-isopropoxyethanol 174.66
    2,2,2-trifluoroethanol 63.89
    methyl butyrate 66.84

    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