Pyrrole

Overview IFRA Botanical Request a quote

  • Identifiers

    CAS number
    109-97-7

    Molecular formula
    C4H5N

    SMILES
    C1=CNC=C1

    Safety labels

    Flammable
    Flammable

    Irritant
    Irritant

    Retention indicies (RI)

    • DB5: 762.0

  • Odor profile

    Sweet 83.71%
    Burnt 66.8%
    Nutty 63.92%
    Ethereal 53.62%
    Musty 53.59%
    Tobacco 46.76%
    Smoky 44.52%
    Fishy 44.01%
    Pungent 43.58%
    Phenolic 41.68%

    Scent© AI

  • Properties

    XLogP3-AA
    0.7

    Molecular weight
    67.09 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Ultra fast

    Melting point expt.

    • -23.4 °C
    • -24 °C

    Boiling point

    • 129.7 °C
    • 130.00 to 131.00 °C. @ 760.00 mm Hg

    Flash point est.
    43.98 ˚C

    Flash point expt.

    • 102 °F (39 °C) (CLOSED CUP)

    Solubility expt.

    • Soluble in alcohol, ether and dilute acids. Also soluble in most organic chemicals.
    • Water solubility: 4.5X10+4 mg/l @ 25 °C
    • 45 mg/mL at 25 °C
    • Soluble in most fixed oils; Slightly soluble in water
    • Soluble (in ethanol)

  • Synonyms

    • PYRROLE
    • 1H-Pyrrole
    • 109-97-7
    • Divinylenimine
    • Imidole
    • Azole
    • Pyrrol
    • Monopyrrole
    • Divinyleneimine
    • 1-Aza-2,4-cyclopentadiene
    • 30604-81-0
    • FEMA No. 3386
    • Pyrrole-15N
    • NSC 62777
    • CCRIS 2933
    • HSDB 119
    • CHEBI:19203
    • EINECS 203-724-7
    • UNII-86S1ZD6L2C
    • NSC-62777
    • (1H-Pyrrole)x
    • PYROLLE
    • 86S1ZD6L2C
    • DTXSID5021910
    • AI3-18817
    • MFCD00005216
    • DTXCID201910
    • 26120-22-9
    • Pyrroles
    • C4H5N
    • Pyrrhol
    • Pyrole
    • beta-pyrrole
    • a pyrrole
    • pyrrole-
    • Pyrrole, Reagent
    • Polypyrrole (undoped, extent of labeling: ~20 wt. % loading, composite with carbon black)
    • 1-H-pyrrole
    • Pyrrole1539
    • 1-aza-cyclopentadiene
    • PYRROLE [FHFI]
    • PYRROLE [HSDB]
    • PYRROLE [FCC]
    • 1H-PYRROLE [MI]
    • Epitope ID:136031
    • WLN: T5MJ
    • Pyrrole, analytical standard
    • CHEMBL16225
    • Pyrrole, reagent grade, 98%
    • QSPL 001
    • CHEBI:35556
    • FEMA 3386
    • Pyrrole, >=98%, FCC, FG
    • NSC62777
    • NSC72470
    • STR00296
    • Tox21_303910
    • BBL011520
    • NSC-72470
    • STL146636
    • AKOS000120094
    • FP14738
    • NCGC00357161-01
    • BP-21154
    • CAS-109-97-7
    • 1H-Pyrrole; Azole; Divinylenimine; Imidole
    • DB-003771
    • NS00014390
    • P0574
    • EN300-20590
    • C19907
    • H27771
    • A802120
    • InChI=1/C4H5N/c1-2-4-5-3-1/h1-5
    • Q242627
    • F2190-0643
    • Z104479036
    • 107760-17-8
    • 203-724-7

  • Applications

    Because of its electron-rich five-membered heterocycle, Pyrrole (CAS 109-97-7) finds extensive use across advanced chemical synthesis: it is a key building block for artificial porphyrins, heme and chlorophyll analogues, the monomer for conductive polypyrrole employed in batteries, supercapacitors, sensors and biomedical scaffolds; in pharmaceuticals, the pyrrole motif appears in numerous anti-inflammatory, antibacterial, anticancer and kinase-inhibiting drugs, as well as in pesticides and plant growth regulators; in the pigment industry it contributes to thermally stable phthalocyanine and azo dyes, while in flavor chemistry it imparts roasted, caramel notes; moreover, its metal-chelating ability and participation in cross-coupling make pyrrole an important reagent for homogeneous catalysts, optoelectronic materials and cutting-edge polymerization processes.

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 564.11
    methanol 650.02
    isopropanol 337.59
    water 28.74
    ethyl acetate 92.93
    n-propanol 354.25
    acetone 313.78
    n-butanol 245.3
    acetonitrile 172.6
    DMF 620.67
    toluene 18.61
    isobutanol 207.0
    1,4-dioxane 180.7
    methyl acetate 152.18
    THF 346.09
    2-butanone 195.74
    n-pentanol 160.91
    sec-butanol 215.85
    n-hexane 12.95
    ethylene glycol 370.97
    NMP 320.93
    cyclohexane 12.02
    DMSO 571.06
    n-butyl acetate 78.75
    n-octanol 59.46
    chloroform 114.94
    n-propyl acetate 65.85
    acetic acid 536.8
    dichloromethane 76.88
    cyclohexanone 132.28
    propylene glycol 402.96
    isopropyl acetate 43.5
    DMAc 407.93
    2-ethoxyethanol 250.36
    isopentanol 137.79
    n-heptane 21.37
    ethyl formate 70.49
    1,2-dichloroethane 51.45
    n-hexanol 168.24
    2-methoxyethanol 454.85
    isobutyl acetate 44.67
    tetrachloromethane 26.93
    n-pentyl acetate 39.25
    transcutol 338.59
    n-heptanol 71.01
    ethylbenzene 9.94
    MIBK 51.0
    2-propoxyethanol 280.45
    tert-butanol 223.49
    MTBE 97.13
    2-butoxyethanol 139.25
    propionic acid 308.45
    o-xylene 16.95
    formic acid 282.51
    diethyl ether 108.05
    m-xylene 14.5
    p-xylene 16.3
    chlorobenzene 28.86
    dimethyl carbonate 66.13
    n-octane 5.08
    formamide 281.23
    cyclopentanone 243.62
    2-pentanone 112.77
    anisole 47.58
    cyclopentyl methyl ether 110.62
    gamma-butyrolactone 215.95
    1-methoxy-2-propanol 320.8
    pyridine 135.65
    3-pentanone 94.45
    furfural 159.68
    n-dodecane 3.93
    diethylene glycol 277.61
    diisopropyl ether 23.25
    tert-amyl alcohol 152.35
    acetylacetone 88.0
    n-hexadecane 4.08
    acetophenone 45.57
    methyl propionate 123.44
    isopentyl acetate 55.19
    trichloroethylene 105.91
    n-nonanol 50.84
    cyclohexanol 106.92
    benzyl alcohol 65.25
    2-ethylhexanol 73.71
    isooctanol 48.07
    dipropyl ether 92.43
    1,2-dichlorobenzene 23.46
    ethyl lactate 60.01
    propylene carbonate 85.08
    n-methylformamide 322.62
    2-pentanol 132.13
    n-pentane 16.84
    1-propoxy-2-propanol 200.28
    1-methoxy-2-propyl acetate 79.71
    2-(2-methoxypropoxy) propanol 96.81
    mesitylene 8.86
    ε-caprolactone 96.59
    p-cymene 15.41
    epichlorohydrin 156.47
    1,1,1-trichloroethane 55.33
    2-aminoethanol 478.44
    morpholine-4-carbaldehyde 261.63
    sulfolane 241.25
    2,2,4-trimethylpentane 8.12
    2-methyltetrahydrofuran 174.93
    n-hexyl acetate 52.35
    isooctane 5.65
    2-(2-butoxyethoxy)ethanol 138.2
    sec-butyl acetate 35.18
    tert-butyl acetate 42.02
    decalin 5.44
    glycerin 443.86
    diglyme 217.08
    acrylic acid 299.61
    isopropyl myristate 22.21
    n-butyric acid 205.11
    acetyl acetate 48.22
    di(2-ethylhexyl) phthalate 30.58
    ethyl propionate 54.77
    nitromethane 387.62
    1,2-diethoxyethane 80.44
    benzonitrile 47.8
    trioctyl phosphate 22.09
    1-bromopropane 40.77
    gamma-valerolactone 223.7
    n-decanol 38.55
    triethyl phosphate 25.27
    4-methyl-2-pentanol 55.94
    propionitrile 127.82
    vinylene carbonate 72.88
    1,1,2-trichlorotrifluoroethane 229.57
    DMS 46.49
    cumene 10.0
    2-octanol 35.96
    2-hexanone 80.29
    octyl acetate 34.42
    limonene 27.39
    1,2-dimethoxyethane 207.64
    ethyl orthosilicate 25.67
    tributyl phosphate 24.56
    diacetone alcohol 94.47
    N,N-dimethylaniline 39.64
    acrylonitrile 154.19
    aniline 72.39
    1,3-propanediol 341.05
    bromobenzene 19.07
    dibromomethane 49.53
    1,1,2,2-tetrachloroethane 96.99
    2-methyl-cyclohexyl acetate 39.53
    tetrabutyl urea 39.06
    diisobutyl methanol 32.63
    2-phenylethanol 61.04
    styrene 14.72
    dioctyl adipate 34.84
    dimethyl sulfate 101.64
    ethyl butyrate 52.56
    methyl lactate 121.77
    butyl lactate 51.66
    diethyl carbonate 32.56
    propanediol butyl ether 139.72
    triethyl orthoformate 40.98
    p-tert-butyltoluene 15.54
    methyl 4-tert-butylbenzoate 47.15
    morpholine 272.5
    tert-butylamine 135.78
    n-dodecanol 30.7
    dimethoxymethane 202.35
    ethylene carbonate 58.98
    cyrene 85.79
    2-ethoxyethyl acetate 56.89
    2-ethylhexyl acetate 42.32
    1,2,4-trichlorobenzene 36.83
    4-methylpyridine 85.77
    dibutyl ether 38.97
    2,6-dimethyl-4-heptanol 32.63
    DEF 141.38
    dimethyl isosorbide 92.5
    tetrachloroethylene 72.74
    eugenol 59.91
    triacetin 56.52
    span 80 97.01
    1,4-butanediol 179.5
    1,1-dichloroethane 65.39
    2-methyl-1-pentanol 94.18
    methyl formate 169.89
    2-methyl-1-butanol 151.0
    n-decane 6.47
    butyronitrile 96.93
    3,7-dimethyl-1-octanol 47.2
    1-chlorooctane 19.52
    1-chlorotetradecane 8.69
    n-nonane 6.39
    undecane 4.8
    tert-butylcyclohexane 6.54
    cyclooctane 4.08
    cyclopentanol 192.21
    tetrahydropyran 157.62
    tert-amyl methyl ether 71.72
    2,5,8-trioxanonane 153.63
    1-hexene 37.79
    2-isopropoxyethanol 147.68
    2,2,2-trifluoroethanol 158.57
    methyl butyrate 71.12

    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
Tamarind 1 dried fruit Tamarindus indica L., fam. Leguminosae 0.5%
Orris butter 8002-73-1 Iris florentina L., fam. Iridaceae 0.01%
Truffle, white (Italy) Tuber magnatum Pico, fam. Ascomycetae 0.5%
Tamarind 3 fruit Tamarindus indica L., fam. Leguminosae 0.1%
Colocasia esculenta (Taro) Colocasia esculenta (L.) Schott, fam. Araceae 0.4%