2-Phenylpropionic acid

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  • Identifiers

    CAS number
    492-37-5

    Molecular formula
    C9H10O2

    SMILES
    CC(C1=CC=CC=C1)C(=O)O

    Safety labels

    Irritant
    Irritant

  • Odor profile

    Fragrance
    Floral 82.78%
    Sweet 80.41%
    Honey 75.15%
    Balsamic 48.73%
    Powdery 47.06%
    Rose 44.24%
    Chocolate 35.03%
    Animal 33.43%
    Fruity 29.66%
    Cocoa 29.44%

     

    Flavor
    Sweet 49.93%
    Floral 48.01%
    Honey 43.43%
    Waxy 37.57%
    Sour 32.76%
    Mild 28.63%
    Rose 28.14%
    Balsam 27.7%
    Odorless 24.03%
    Honeysuckle 23.64%

     

    Odor impact est.
    High

  • Properties

    XLogP3-AA
    1.9

    pKa est.
    6.96 (neutral)

    Molecular weight
    150.17 g/mol

    Vapor pressure est.

    • hPa @ 20°C
    • hPa @ 25°C

    Evaporation rate
    Very slow

    Boiling point est.
    257°C

    Flash point

    • 133.72 ˚C est.

  • Synonyms

    • 2-Phenylpropionic acid
    • 492-37-5
    • 2-Phenylpropanoic acid
    • Hydratropic acid
    • DL-2-Phenylpropionic Acid
    • (+/-)-2-Phenylpropionic acid
    • alpha-Methylphenylacetic acid
    • Hydratropasaeure
    • alpha-Methylbenzeneacetic acid
    • 2-Phenyl-propionic acid
    • Benzeneacetic acid, .alpha.-methyl-
    • ALPHA-PHENYLPROPIONIC ACID
    • MFCD00002650
    • (+-)-Hydratropasaeure
    • .alpha.-Methylphenylacetic acid
    • (+-)-hydratropic acid
    • (+/-)-2-phenylpropanoic acid
    • .alpha.-Methylbenzeneacetic acid
    • (+/-)-Hydratropic acid
    • .alpha.-Phenylpropionic acid
    • (R)-(-)-Hydratropic acid
    • UNII-CH15E393A2
    • CHEBI:48526
    • Benzeneacetic acid, alpha-methyl-
    • DL-PPA
    • 2-Phenylpropionate
    • alpha-Phenylpropioic acid
    • EINECS 207-752-0
    • NSC 42872
    • NSC-42872
    • Propanoic acid, 2-phenyl
    • NSC-245033
    • dl-.alpha.-Phenylpropionic acid
    • YPGCWEMNNLXISK-UHFFFAOYSA-
    • DTXSID80862027
    • Loxoprofen impurity
    • CH15E393A2
    • NSC 245033
    • a-Methylbenzeneacetic acid
    • DL-?-phenylpropionic acid
    • 2-Phenylpropionicacid
    • 2328-24-7
    • (S)-(+)-Hydratropic acid
    • 2-phenyl propionic acid
    • alpha-Phenylpropioate
    • Benzeneacetic acid, .alpha.-methyl-, (R)-
    • Benzeneacetic acid, .alpha.-methyl-, (S)-
    • 2-phenyl propanoic acid
    • alpha-phenyl propionic acid
    • propanoic acid, 2-phenyl-
    • SCHEMBL3418
    • (?)-2-Phenylpropionic acid
    • dl-alpha-Phenylpropionic acid
    • (RS)-2-phenylpropionic acid
    • (+/-)2-phenylpropionic acid
    • racemic 2-phenylpropionic acid
    • 2-Phenylpropionic acid, 97%
    • (rac.)-2-phenylpropionic acid
    • CHEMBL370925
    • (+/-) 2-phenylpropionic acid
    • DTXCID30223422
    • alpha-methyl-benzeneacetic acid /OD/ 2-phenylpropionic acid
    • BCP14307
    • BCP16764
    • NSC42872
    • STR03808
    • NSC245032
    • NSC245033
    • s6321
    • STL164373
    • AKOS005206767
    • AC-3206
    • CS-W016324
    • FP35013
    • HY-W015608
    • PS-4663
    • PD099465
    • SY004963
    • SY020842
    • SY021075
    • Hydratropic acid [MeSH: hydratropic acid]
    • DB-021501
    • NS00006882
    • P0699
    • EN300-69310
    • F13477
    • 2-Phenylpropionic acid [MeSH: hydratropic acid]
    • racemic (+)-alpha-methyl-alpha-phenylacetic acid
    • Q27121253
    • F0001-1284
    • Z756118128

  • Applications

    2-Phenylpropionic acid (alpha-phenylpropionic acid) is primarily used as an organic building block and intermediate in pharmaceutical synthesis, often serving as a chiral starting material or precursor for the production of NSAID-related and other therapeutic compounds. It is also employed in fragrance and flavor chemistry as a precursor to aroma-related esters and other odor-active derivatives. In cosmetics and personal care, it may function as a starting material for synthesis of cosmetic ingredients and fragrance components. In industrial manufacturing, it serves as a versatile intermediate for the preparation of specialty chemicals, resins, and other workhorse transformations (e.g., esterifications, amidations) used in various downstream products. In research and development, it is used as a model substrate for asymmetric synthesis, catalysis studies, and method development. The use of this acid and its derivatives is subject to local regulations and formulation limits.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 321.9
    methanol 309.61
    isopropanol 293.92
    water 4.76
    ethyl acetate 185.75
    n-propanol 254.93
    acetone 274.27
    n-butanol 216.41
    acetonitrile 257.53
    DMF 1020.74
    toluene 67.56
    isobutanol 183.14
    1,4-dioxane 499.31
    methyl acetate 186.47
    THF 413.22
    2-butanone 234.56
    n-pentanol 151.77
    sec-butanol 213.26
    n-hexane 12.13
    ethylene glycol 121.86
    NMP 458.02
    cyclohexane 10.29
    DMSO 691.16
    n-butyl acetate 131.47
    n-octanol 118.76
    chloroform 296.65
    n-propyl acetate 105.48
    acetic acid 158.57
    dichloromethane 400.8
    cyclohexanone 256.46
    propylene glycol 117.14
    isopropyl acetate 107.03
    DMAc 503.09
    2-ethoxyethanol 225.02
    isopentanol 164.38
    n-heptane 16.5
    ethyl formate 143.14
    1,2-dichloroethane 265.44
    n-hexanol 191.4
    2-methoxyethanol 345.24
    isobutyl acetate 61.78
    tetrachloromethane 35.76
    n-pentyl acetate 87.83
    transcutol 395.34
    n-heptanol 121.62
    ethylbenzene 59.49
    MIBK 124.62
    2-propoxyethanol 276.59
    tert-butanol 306.81
    MTBE 154.95
    2-butoxyethanol 172.57
    propionic acid 189.21
    o-xylene 70.15
    formic acid 84.75
    diethyl ether 166.8
    m-xylene 75.16
    p-xylene 64.91
    chlorobenzene 93.36
    dimethyl carbonate 94.26
    n-octane 10.44
    formamide 206.42
    cyclopentanone 353.68
    2-pentanone 194.98
    anisole 139.79
    cyclopentyl methyl ether 152.79
    gamma-butyrolactone 415.52
    1-methoxy-2-propanol 294.92
    pyridine 182.87
    3-pentanone 139.66
    furfural 261.02
    n-dodecane 11.11
    diethylene glycol 229.66
    diisopropyl ether 49.5
    tert-amyl alcohol 226.37
    acetylacetone 183.29
    n-hexadecane 12.21
    acetophenone 115.33
    methyl propionate 171.49
    isopentyl acetate 110.82
    trichloroethylene 391.93
    n-nonanol 103.76
    cyclohexanol 126.06
    benzyl alcohol 107.56
    2-ethylhexanol 104.37
    isooctanol 95.93
    dipropyl ether 104.02
    1,2-dichlorobenzene 94.8
    ethyl lactate 75.84
    propylene carbonate 190.57
    n-methylformamide 377.54
    2-pentanol 148.5
    n-pentane 11.62
    1-propoxy-2-propanol 196.2
    1-methoxy-2-propyl acetate 139.91
    2-(2-methoxypropoxy) propanol 141.69
    mesitylene 51.08
    ε-caprolactone 198.08
    p-cymene 47.27
    epichlorohydrin 432.58
    1,1,1-trichloroethane 148.56
    2-aminoethanol 202.27
    morpholine-4-carbaldehyde 404.17
    sulfolane 487.55
    2,2,4-trimethylpentane 11.48
    2-methyltetrahydrofuran 251.65
    n-hexyl acetate 124.22
    isooctane 10.93
    2-(2-butoxyethoxy)ethanol 200.36
    sec-butyl acetate 69.36
    tert-butyl acetate 118.2
    decalin 13.84
    glycerin 145.1
    diglyme 330.52
    acrylic acid 150.35
    isopropyl myristate 61.71
    n-butyric acid 181.14
    acetyl acetate 85.2
    di(2-ethylhexyl) phthalate 58.08
    ethyl propionate 99.03
    nitromethane 326.36
    1,2-diethoxyethane 146.61
    benzonitrile 112.74
    trioctyl phosphate 54.33
    1-bromopropane 133.85
    gamma-valerolactone 394.19
    n-decanol 84.81
    triethyl phosphate 53.71
    4-methyl-2-pentanol 91.6
    propionitrile 188.08
    vinylene carbonate 170.15
    1,1,2-trichlorotrifluoroethane 194.91
    DMS 90.85
    cumene 49.91
    2-octanol 83.04
    2-hexanone 123.99
    octyl acetate 81.45
    limonene 63.47
    1,2-dimethoxyethane 304.3
    ethyl orthosilicate 52.21
    tributyl phosphate 52.85
    diacetone alcohol 188.68
    N,N-dimethylaniline 111.4
    acrylonitrile 232.5
    aniline 100.02
    1,3-propanediol 226.92
    bromobenzene 84.66
    dibromomethane 231.97
    1,1,2,2-tetrachloroethane 285.85
    2-methyl-cyclohexyl acetate 82.79
    tetrabutyl urea 83.15
    diisobutyl methanol 66.45
    2-phenylethanol 124.9
    styrene 63.57
    dioctyl adipate 78.58
    dimethyl sulfate 167.43
    ethyl butyrate 102.77
    methyl lactate 110.94
    butyl lactate 81.48
    diethyl carbonate 69.2
    propanediol butyl ether 143.49
    triethyl orthoformate 67.65
    p-tert-butyltoluene 44.94
    methyl 4-tert-butylbenzoate 134.88
    morpholine 449.67
    tert-butylamine 177.14
    n-dodecanol 67.33
    dimethoxymethane 316.96
    ethylene carbonate 141.81
    cyrene 148.49
    2-ethoxyethyl acetate 118.91
    2-ethylhexyl acetate 80.35
    1,2,4-trichlorobenzene 107.86
    4-methylpyridine 182.88
    dibutyl ether 83.61
    2,6-dimethyl-4-heptanol 66.45
    DEF 251.21
    dimethyl isosorbide 209.33
    tetrachloroethylene 159.16
    eugenol 134.77
    triacetin 110.58
    span 80 127.8
    1,4-butanediol 118.62
    1,1-dichloroethane 236.14
    2-methyl-1-pentanol 126.34
    methyl formate 250.59
    2-methyl-1-butanol 154.12
    n-decane 16.57
    butyronitrile 167.05
    3,7-dimethyl-1-octanol 93.28
    1-chlorooctane 63.55
    1-chlorotetradecane 29.32
    n-nonane 15.09
    undecane 13.55
    tert-butylcyclohexane 15.82
    cyclooctane 6.03
    cyclopentanol 165.8
    tetrahydropyran 264.02
    tert-amyl methyl ether 119.1
    2,5,8-trioxanonane 244.68
    1-hexene 56.86
    2-isopropoxyethanol 157.6
    2,2,2-trifluoroethanol 80.89
    methyl butyrate 137.83

    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