Aspirin

Overview IFRA Request a quote

  • Identifiers

    CAS number
    50-78-2

    Molecular formula
    C9H8O4

    SMILES
    CC(=O)OC1=CC=CC=C1C(=O)O

    Safety labels

    Irritant
    Irritant

  • Odor profile

    Fragrance
    Phenolic 57.46%
    Odorless 52.53%
    Burnt 34.9%
    Animal 34.25%
    Balsamic 32.6%
    Sour 31.7%
    Aromatic 31.61%
    Floral 28.31%
    Medicinal 26.37%
    Pungent 25.39%

     

    Flavor
    Sweet 60.33%
    Phenolic 42.95%
    Mild 34.67%
    Odorless 33.77%
    Balsam 33.47%
    Sour 33.3%
    Powdery 32.49%
    Nutty 31.36%
    Balsamic 30.01%
    Faint 30.01%

     

    Odor impact est.
    Low

  • Properties

    XLogP3-AA
    1.2

    pKa est.
    6.61 (neutral)

    Molecular weight
    180.16 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Ultra slow

    Melting point expt.

    • 275 °F (NTP, 1992)
    • 138-140
    • 135 °C (rapid heating)
    • 135 °C
    • 275 °F

    Boiling point

    • 284 °F at 760 mmHg (decomposes) (NTP, 1992)
    • 140 °C
    • 284 °F (decomposes)
    • 284 °F (Decomposes)

    Flash point

    • 171.03 ˚C est.
    • 482 °F (NTP, 1992)

    Solubility expt.

    • less than 1 mg/mL at 73 °F (NTP, 1992)
    • 10 mg/mL
    • 1 g sol in: 300 mL water at 25 °C, 100 mL water at 37 °C, 5 mL alcohol, 17 mL chloroform, 10-15 mL ether; less sol in anhydrous ether
    • In water, 4,600 mg/L at 25 °C
    • Solubility in water, g/100ml at 15 °C: 0.25 (poor)
    • (77 °F): 0.3%

  • Synonyms

    • aspirin
    • ACETYLSALICYLIC ACID
    • 50-78-2
    • 2-Acetoxybenzoic acid
    • 2-(Acetyloxy)benzoic acid
    • Acetosal
    • O-Acetylsalicylic acid
    • o-Acetoxybenzoic acid
    • Acenterine
    • Acetophen
    • Acylpyrin
    • Easprin
    • Ecotrin
    • Salicylic acid acetate
    • Acetosalin
    • Aspirdrops
    • Polopiryna
    • Salcetogen
    • Aceticyl
    • Acetonyl
    • Acetylin
    • Acetylsalicylate
    • Acidum acetylsalicylicum
    • Benaspir
    • Colfarit
    • Empirin
    • Endydol
    • Measurin
    • Rhodine
    • Saletin
    • o-Carboxyphenyl acetate
    • Enterosarein
    • Enterosarine
    • Acetisal
    • Acetylsal
    • Aspirine
    • Bialpirinia
    • Entericin
    • Enterophen
    • Micristin
    • Pharmacin
    • Premaspin
    • Salacetin
    • Solpyron
    • Temperal
    • Acesal
    • Acisal
    • Asagran
    • Asteric
    • Duramax
    • Ecolen
    • Extren
    • Globoid
    • Helicon
    • Idragin
    • Rhonal
    • Aspro
    • Novid
    • Rheumintabletten
    • Yasta
    • Solprin acid
    • Benzoic acid, 2-(acetyloxy)-
    • 2-acetyloxybenzoic acid
    • Acimetten
    • Bialpirina
    • Claradin
    • Clariprin
    • Delgesic
    • Entrophen
    • Globentyl
    • Neuronika
    • Acetilum acidulatum
    • Cemirit
    • Decaten
    • Levius
    • Pirseal
    • Solfrin
    • Acetilsalicilico
    • Adiro
    • Aspec
    • Acetosalic acid
    • Dolean pH 8
    • Triple-sal
    • Spira-Dine
    • ZORprin
    • Contrheuma retard
    • Bi-prin
    • XAXA
    • Acido acetilsalicilico
    • Acide acetylsalicylique
    • Persistin
    • Bayer
    • 2-Carboxyphenyl acetate
    • A.S.A. empirin
    • ASA
    • 8-hour Bayer
    • Endosprin
    • Kapsazal
    • Asatard
    • Durlaza
    • Bayer Plus
    • Acetylsalicylsaure
    • Rheumin tabletten
    • Solprin
    • acetyl salicylic acid
    • Tasprin
    • Nu-seals aspirin
    • Salicylic acid, acetate
    • Acido O-acetil-benzoico
    • Kyselina acetylsalicylova
    • 2-Acetoxybenzenecarboxylic acid
    • Acetylsalicylsaeure
    • Azetylsalizylsaeure
    • SP 189
    • St. Joseph Aspirin for Adults
    • A.S.A.
    • St. Joseph
    • Kyselina 2-acetoxybenzoova
    • AC 5230
    • Acetylsalicyclic acid
    • Acetylsalicylicum acidum
    • Aspropharm
    • Cardioaspirin
    • Acetard
    • CHEBI:15365
    • acetyl salicylate
    • benzoic acid, 2-acetoxy-
    • S-211

  • Applications

    Aspirin (acetylsalicylic acid, CAS 50-78-2) is primarily used as an active pharmaceutical ingredient with analgesic, antipyretic and anti-inflammatory effects. It also serves as a starting material and intermediate in organic synthesis to prepare acetylated derivatives and salicylic acid based compounds for pharmaceutical research and development. In cosmetics and personal care, it may be evaluated as a source of salicylic acid or as a building block for related derivatives in topical formulations. In laboratory settings, aspirin is used as a reagent and educational sample to demonstrate esterification and hydrolysis reactions and to support early-stage product development related to acetylated phenolics.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 175.74
    methanol 285.94
    isopropanol 101.4
    water 3.98
    ethyl acetate 79.25
    n-propanol 102.45
    acetone 248.95
    n-butanol 73.57
    acetonitrile 89.68
    DMF 763.15
    toluene 6.48
    isobutanol 57.32
    1,4-dioxane 261.94
    methyl acetate 108.25
    THF 353.35
    2-butanone 105.46
    n-pentanol 57.91
    sec-butanol 63.54
    n-hexane 2.79
    ethylene glycol 94.22
    NMP 455.81
    cyclohexane 1.59
    DMSO 752.59
    n-butyl acetate 41.41
    n-octanol 31.44
    chloroform 24.56
    n-propyl acetate 58.5
    acetic acid 114.27
    dichloromethane 61.42
    cyclohexanone 109.52
    propylene glycol 62.75
    isopropyl acetate 46.44
    DMAc 445.37
    2-ethoxyethanol 155.14
    isopentanol 53.46
    n-heptane 3.0
    ethyl formate 101.32
    1,2-dichloroethane 51.8
    n-hexanol 44.82
    2-methoxyethanol 306.27
    isobutyl acetate 27.04
    tetrachloromethane 2.77
    n-pentyl acetate 30.92
    transcutol 146.57
    n-heptanol 25.84
    ethylbenzene 12.16
    MIBK 52.75
    2-propoxyethanol 146.77
    tert-butanol 113.51
    MTBE 48.75
    2-butoxyethanol 61.36
    propionic acid 82.8
    o-xylene 13.27
    formic acid 104.83
    diethyl ether 58.88
    m-xylene 12.04
    p-xylene 15.07
    chlorobenzene 15.95
    dimethyl carbonate 100.01
    n-octane 1.99
    formamide 203.79
    cyclopentanone 206.03
    2-pentanone 88.06
    anisole 60.5
    cyclopentyl methyl ether 75.05
    gamma-butyrolactone 287.57
    1-methoxy-2-propanol 197.09
    pyridine 54.16
    3-pentanone 60.57
    furfural 205.37
    n-dodecane 3.14
    diethylene glycol 161.12
    diisopropyl ether 14.76
    tert-amyl alcohol 65.69
    acetylacetone 133.51
    n-hexadecane 3.45
    acetophenone 62.41
    methyl propionate 107.8
    isopentyl acetate 34.61
    trichloroethylene 61.78
    n-nonanol 30.28
    cyclohexanol 44.96
    benzyl alcohol 55.88
    2-ethylhexanol 26.57
    isooctanol 21.51
    dipropyl ether 36.46
    1,2-dichlorobenzene 22.52
    ethyl lactate 62.0
    propylene carbonate 126.81
    n-methylformamide 316.35
    2-pentanol 42.2
    n-pentane 2.28
    1-propoxy-2-propanol 81.73
    1-methoxy-2-propyl acetate 75.17
    2-(2-methoxypropoxy) propanol 79.79
    mesitylene 10.68
    ε-caprolactone 108.13
    p-cymene 13.34
    epichlorohydrin 245.53
    1,1,1-trichloroethane 19.99
    2-aminoethanol 110.78
    morpholine-4-carbaldehyde 367.64
    sulfolane 355.17
    2,2,4-trimethylpentane 2.05
    2-methyltetrahydrofuran 123.68
    n-hexyl acetate 48.32
    isooctane 1.74
    2-(2-butoxyethoxy)ethanol 91.86
    sec-butyl acetate 31.48
    tert-butyl acetate 50.84
    decalin 3.5
    glycerin 120.58
    diglyme 154.67
    acrylic acid 84.3
    isopropyl myristate 27.7
    n-butyric acid 74.52
    acetyl acetate 57.56
    di(2-ethylhexyl) phthalate 32.5
    ethyl propionate 64.93
    nitromethane 285.18
    1,2-diethoxyethane 55.3
    benzonitrile 48.58
    trioctyl phosphate 26.63
    1-bromopropane 22.1
    gamma-valerolactone 283.63
    n-decanol 26.55
    triethyl phosphate 31.07
    4-methyl-2-pentanol 25.74
    propionitrile 66.08
    vinylene carbonate 113.01
    1,1,2-trichlorotrifluoroethane 121.57
    DMS 57.45
    cumene 12.86
    2-octanol 19.15
    2-hexanone 59.84
    octyl acetate 36.48
    limonene 17.38
    1,2-dimethoxyethane 256.35
    ethyl orthosilicate 26.51
    tributyl phosphate 28.52
    diacetone alcohol 91.68
    N,N-dimethylaniline 51.03
    acrylonitrile 100.46
    aniline 27.41
    1,3-propanediol 126.85
    bromobenzene 12.21
    dibromomethane 28.13
    1,1,2,2-tetrachloroethane 49.86
    2-methyl-cyclohexyl acetate 40.52
    tetrabutyl urea 47.33
    diisobutyl methanol 18.96
    2-phenylethanol 47.7
    styrene 12.05
    dioctyl adipate 44.53
    dimethyl sulfate 179.64
    ethyl butyrate 47.14
    methyl lactate 112.36
    butyl lactate 38.54
    diethyl carbonate 38.45
    propanediol butyl ether 61.04
    triethyl orthoformate 35.06
    p-tert-butyltoluene 12.4
    methyl 4-tert-butylbenzoate 68.97
    morpholine 218.13
    tert-butylamine 44.55
    n-dodecanol 22.77
    dimethoxymethane 351.54
    ethylene carbonate 90.75
    cyrene 109.67
    2-ethoxyethyl acetate 47.77
    2-ethylhexyl acetate 26.22
    1,2,4-trichlorobenzene 28.58
    4-methylpyridine 61.05
    dibutyl ether 29.52
    2,6-dimethyl-4-heptanol 18.96
    DEF 141.1
    dimethyl isosorbide 134.27
    tetrachloroethylene 23.46
    eugenol 73.16
    triacetin 57.11
    span 80 61.03
    1,4-butanediol 58.4
    1,1-dichloroethane 28.46
    2-methyl-1-pentanol 42.78
    methyl formate 292.78
    2-methyl-1-butanol 49.27
    n-decane 3.98
    butyronitrile 62.08
    3,7-dimethyl-1-octanol 29.4
    1-chlorooctane 15.5
    1-chlorotetradecane 9.8
    n-nonane 3.3
    undecane 3.53
    tert-butylcyclohexane 3.76
    cyclooctane 1.01
    cyclopentanol 72.34
    tetrahydropyran 85.21
    tert-amyl methyl ether 42.19
    2,5,8-trioxanonane 128.18
    1-hexene 12.84
    2-isopropoxyethanol 84.01
    2,2,2-trifluoroethanol 53.91
    methyl butyrate 84.77

    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